Editing Great Pyramid of Giza (section)

==Interior==
[[File:Great Pyramid S-N Diagram.svg|thumb|upright=1.2|Elevation diagram of the interior structures of the Great Pyramid viewed from the east. The inner and outer lines indicate the pyramid's present and original profiles.
{{unbulleted list
|'''1.''' [[#Original entrance|Original entrance]], [[Great Pyramid#North Face Corridor|North Face Corridor]]
|'''2.''' [[#Robbers' Tunnel|Robbers' Tunnel]] (tourist entrance)
|'''3, 4.''' [[#Descending Passage|Descending Passage]]
|'''5.''' [[#Subterranean Chamber|Subterranean Chamber]]
|'''6.''' [[#Ascending Passage|Ascending Passage]]
|'''7.''' [[#Queen's Chamber|Queen's Chamber]] and its "air-shafts"
|'''8.''' Horizontal Passage
|'''9.''' [[#Grand Gallery|Grand Gallery]]
|'''10.''' [[#King's Chamber|King's Chamber]] and its [[#Air shafts|"air-shafts"]]
|'''11.''' [[#Well Shaft and Grotto|Grotto and Well Shaft]]
}}
]]
The internal structure consists of three main chambers (the King's, Queen's and Subterranean Chambers), the Grand Gallery and various corridors and shafts. None of the interior walls were decorated or inscribed, as was the norm for tombs of the 4th dynasty, apart from the marks and names of work-gangs left on blocks of the relieving chambers.{{sfn|Kanawati|2005|p=55}}

There are two entrances into the pyramid: the original and a forced passage, which meet at a junction. From there, one passage descends into the Subterranean Chamber, while the other ascends to the Grand Gallery. From the beginning of the gallery three paths can be taken:

* a vertical shaft that leads down, past a grotto, to meet the descending passage
* a horizontal corridor leading to the Queen's Chamber
* and the path up the gallery itself to the King's Chamber that contains the sarcophagus.

Both the King's and Queen's Chamber have a pair of small "air-shafts". Above the King's Chamber are a series of five relieving chambers.

=== Entrances ===
==== Original entrance ====
The original entrance is on the north side, {{convert|15|royal cubit|m+ft|1|lk=in}} east of the centreline of the pyramid. Before the removal of the casing in the Middle Ages, the pyramid was entered through a hole in the 19th layer of masonry, approximately {{convert|17|m|ft}} above the pyramid's base level. The height of that layer – {{convert|96|cm|ft}} – corresponds to the size of the entrance tunnel that is commonly called the Descending Passage.{{sfn|Maragioglio|Rinaldi|1965b}}{{sfn|Haase|2004b|p=15}} According to [[Strabo]] (64–24 BC) a movable stone could be raised to enter this sloping corridor; however, it is not known if it was a later addition or original.[[File:Cheops-Pyramid@Eingaenge.JPG|left|thumb|upright|The original entrance (top-left), Robbers' Tunnel (middle-right)]]

A row of double chevrons diverts weight away from the entrance. Several of these chevron blocks are now missing, as indicated by the slanted faces on which they once rested.

Numerous, mostly modern, graffiti is cut into the stones around the entrance. Most notable is a large, square text of hieroglyphs carved in honor of [[Frederick William IV of Prussia|Frederick William IV]], by [[Karl Richard Lepsius]]'s Prussian expedition to Egypt in 1842.<ref>{{Cite web|title=The Hieroglyphic Inscription Above the Great Pyramid's Entrance|url=http://www.catchpenny.org/gpglyph.html|access-date=}}</ref>

===== North Face Corridor =====
In 2016 the [[Scanpyramids|ScanPyramids]] team detected a cavity behind the entrance chevrons using [[muography]], which was confirmed in 2019 to be a corridor at least {{Convert|5|m|ft}} long, and running horizontal or sloping upwards (thus not parallel to the Descending Passage).<ref>{{Cite news|title=#ScanPyramids – First conclusive findings with muography on Khufu Pyramid|url=http://www.hip.institute/press/HIP_INSTITUTE_CP9_EN.pdf |archive-url=https://web.archive.org/web/20161019155509/http://www.hip.institute/press/HIP_INSTITUTE_CP9_EN.pdf |archive-date=2016-10-19|url-status=live}}</ref><ref>{{Cite web|title=ScanPyramids 2019 English Video Report|date=16 November 2019|url=https://vimeo.com/373622564}}</ref>

In February 2023 the North Face Corridor was explored with an endoscopic camera, revealing a horizontal tunnel with a length of {{Convert|9|m|ft}} and a transverse section of about {{Convert|2 by 2|m|ft}}. Its ceiling is formed by large chevrons, like those visible above the original entrance and also similar to relieving chambers.<ref>{{Cite journal |date=2 March 2023 |title=Precise characterization of a corridor-shaped structure in Khufu's Pyramid by observation of cosmic-ray muons |journal=[[Nature Communications]] |volume=14|bibcode=2023NatCo..14.1144P |last1=Procureur |first1=Sébastien |last2=Morishima |first2=Kunihiro |last3=Kuno |first3=Mitsuaki |last4=Manabe |first4=Yuta |last5=Kitagawa |first5=Nobuko |last6=Nishio |first6=Akira |last7=Gomez |first7=Hector |last8=Attié |first8=David |last9=Sakakibara |first9=Ami |last10=Hikata |first10=Kotaro |last11=Moto |first11=Masaki |last12=Mandjavidze |first12=Irakli |last13=Magnier |first13=Patrick |last14=Lehuraux |first14=Marion |last15=Benoit |first15=Théophile |last16=Calvet |first16=Denis |last17=Coppolani |first17=Xavier |last18=Kebbiri |first18=Mariam |last19=Mas |first19=Philippe |last20=Helal |first20=Hany |last21=Tayoubi |first21=Mehdi |last22=Marini |first22=Benoit |last23=Serikoff |first23=Nicolas |last24=Anwar |first24=Hamada |last25=Steiger |first25=Vincent |last26=Takasaki |first26=Fumihiko |last27=Fujii |first27=Hirofumi |last28=Satoh |first28=Kotaro |last29=Kodama |first29=Hideyo |last30=Hayashi |first30=Kohei |issue=1 |page=1144 |doi=10.1038/s41467-023-36351-0 |pmid=36864018 |pmc=9981702 |s2cid=257259769 |display-authors=1 }}</ref><ref>{{Cite web |title=ScanPyramids North Face Corridor 2023 Report |date=March 2023 |url=https://vimeo.com/803685954}}</ref>

====Robbers' Tunnel====
Today tourists enter the Great Pyramid via the Robbers' Tunnel, which was long ago cut straight through the masonry of the pyramid. The entrance was forced into the 6th and 7th layer of the casing, about {{Convert|7|m|ft}} above the base. After running more or less straight and horizontal for {{Convert|27|m|ft}} it turns sharply left to encounter the blocking stones in the Ascending Passage. It is possible to enter the Descending Passage from this point but access is usually forbidden.{{sfn|Tyldesley|2007|pp=38–40}}

The origin of this Robbers' Tunnel is the subject of much scholarly discussion. According to tradition the opening was made around 820&nbsp;AD by Caliph [[al-Ma'mun]]'s workmen with a battering ram. The digging dislodged the stone in the ceiling of the Descending Passage that hid the entrance to the Ascending Passage, and the noise of that stone falling, then sliding down the Descending Passage alerted them to the need to turn left. Unable to remove these stones, the workmen tunnelled upwards beside them through the softer limestone of the Pyramid until they reached the Ascending Passage.{{sfn|Tyldesley|2007|p=38}}{{sfn|Battutah|2002|p=18}}

Due to historical and archaeological discrepancies, many scholars (with [[Antoine Isaac Silvestre de Sacy|Antoine de Sacy]] perhaps being the first) contend that this story is apocryphal. They argue that it is much more likely that the tunnel had been carved shortly after the pyramid was initially sealed. This tunnel, the scholars continue, was then resealed (likely during the [[New Kingdom of Egypt|Ramesside Restoration]]), and it was this plug that al-Ma'mun's ninth-century expedition cleared away. This theory is furthered by the report of patriarch [[Dionysius I Telmaharoyo]], who claimed that before al-Ma'mun's expedition, there already existed a breach in the pyramid's north face that extended into the structure {{Convert|33|m|ft}} before hitting a dead end. This suggests that some sort of robber's tunnel predated al-Ma'mun, and that the caliph enlarged it and cleared it of debris.{{sfn|Cooperson|2010|pp=170–175}}

=== Descending Passage ===
From the original entrance, a passage descends through the masonry of the pyramid and then into the bedrock beneath it, ultimately leading to the Subterranean Chamber.

It has a slanted height of 4 [[Ancient Egyptian units of measurement|Egyptian feet]] (1.20 m; 3.9&nbsp;ft) and a width of {{convert|2|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}}. Its angle of 26°26'46" corresponds to a ratio of 1 to 2 (rise over run).{{sfn|Dormion|2004|p=284}}

After {{convert|28|m|ft}}, the lower end of the Ascending Passage is reached; a [[c:File:46 edgar.jpg|square hole]] in the ceiling, which is blocked by granite stones and might have originally been concealed. To circumvent these hard stones, a short tunnel was excavated that meets the end of the Robbers' Tunnel. This was expanded over time and fitted with stairs.

The passage continues to descend for another {{convert|72|m|ft}}, now through bedrock instead of the pyramid superstructure. Lazy guides used to block off this part with rubble to avoid having to lead people down and back up the long shaft, until around 1902 when [[Lorenzo Dow Covington|Covington]] installed a padlocked iron grill-door to stop this practice.{{sfn|Edgar|Edgar|1910|p=141}} Near the end of this section, on the west wall, is the connection to the vertical shaft that leads up to the Grand Gallery.

A horizontal shaft connects the end of the Descending Passage to the Subterranean Chamber, It has a length of {{convert|8.84|m|ft|abbr=on}}, width of {{convert|85|cm|ft|abbr=on}} and height of {{convert|91-95|cm|ft|abbr=on}}. A [[c:File:32 edgar.jpg|recess]] is located towards the end of the western wall, slightly larger than the tunnel, the ceiling of which is irregular and undressed.{{sfn|Maragioglio|Rinaldi|1965a|p=30}}

=== Subterranean Chamber ===
The Subterranean Chamber, or "Pit", is the lowest of the three main chambers and the only one dug into the bedrock beneath the pyramid.

Located about {{Convert|27|m|ft|abbr=on}} below base level,{{sfn|Maragioglio|Rinaldi|1965b}} it measures roughly {{convert|16|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} north-south by {{convert|27|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} east-west, with an approximate height of {{Convert|4|m|ft|abbr=on}}.
The western half of the room, apart from the ceiling, is unfinished, with trenches left behind by the quarry-men running east to west. A niche was cut into the northern half of the west wall. The only access, through the Descending Passage, lies on the eastern end of the north wall.

Although seemingly known in antiquity, according to Herodotus and later authors, its existence had been forgotten in the Middle Ages until rediscovery in 1817, when [[Giovanni Battista Caviglia|Giovanni Caviglia]] cleared the rubble blocking the Descending Passage.{{sfn|Perring|1839|p=3, Plate IX}}

Opposing the entrance, a blind corridor runs straight south for {{Convert|11|m|ft|abbr=on}} and continues with a slight bend another {{Convert|5.4|m|ft|abbr=on}}, measuring about {{Convert|0.75|m|ft|abbr=on}} squared. A Greek or Roman character was found on its ceiling with the light of a candle, suggesting that the chamber had indeed been accessible during [[Classical antiquity]].{{sfn|Vyse|1840b|p=290}}

In the middle of the eastern half is a large hole called a Pit Shaft or [[John Shae Perring|Perring]]'s Shaft. The uppermost part may have ancient origins, about {{Convert|2|m|ft|abbr=on}} squared in width and {{Convert|1.5|m|ft|abbr=on}} in depth, diagonally aligned with the chamber. Caviglia and [[Henry Salt (Egyptologist)|Salt]] enlarged it to the depth of about {{Convert|3|m|ft|abbr=on}}.{{sfn|Perring|1839}} In 1837 [[Howard Vyse|Vyse]] directed the shaft to be sunk to a depth of {{Convert|50|ft|m|abbr=on}}, in hopes of discovering the chamber encompassed by water that Herodotus alluded to. It is slightly narrower in width at about {{Convert|1.5|m|ft|abbr=on}}. No chamber was discovered after Perring and his workers had spent one and a half years penetrating the bedrock to the then water level of the Nile, {{Convert|12|m|ft|abbr=on}} further down.{{sfn|Vyse|1840a|pp=223–224}}

The rubble produced during this operation was deposited throughout the chamber. Petrie, visiting in 1880, found the shaft to be partially filled with rainwater that had rushed down the Descending Passage.{{sfn|Petrie|1883|p=60}} In 1909, when the Edgar brothers' surveying activities were encumbered by the material, they moved the sand and smaller stones back into the shaft, leaving the upper part clear.{{sfn|Edgar|Edgar|1910|p=147}} The deep, modern shaft is sometimes mistaken to be part of the original design.

[[Ludwig Borchardt]] suggested that the Subterranean Chamber was originally planned to be the burial place for pharaoh Khufu, but that it was abandoned during construction in favour of a chamber higher up in the pyramid.{{Sfn|Maragioglio|Rinaldi|1965a|p=148}}

<gallery mode="packed" class="center" heights="160">
File:27_edgar.jpg|Rubble from the Pit Shaft excavation still filling the subterranean chamber in 1909
File:30_edgar.jpg|Pit Shaft in the floor, and blind corridor entrance
File:28_edgar.jpg|Niche in the west wall
File:31_edgar.jpg|Descending Passage exiting in the north wall
</gallery>

=== Ascending Passage ===
[[File:49 edgar.jpg|thumb|The upper two granite plugs in the Ascending Passage, seen from the end of the Robbers' Tunnel]]
The Ascending Passage connects the Descending Passage to the Grand Gallery. It is {{convert|75|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} long and of the same width and height as the shaft from which it originates, although its angle is slightly lower at 26°6'.{{sfn|Dormion|2004|p=286}}

The lower end of the shaft is plugged by three granite stones, which were slid down from the Grand Gallery to seal the tunnel. They are {{convert|1.57|m|ft|abbr=on}}, {{convert|1.67|m|ft|abbr=on}} and {{convert|1|m|ft|abbr=on}} long respectively.{{sfn|Dormion|2004|p=286}} The uppermost is heavily damaged, hence it is shorter. The Robbers' Tunnel terminates slightly below the stones, so a short tunnel was dug around them to access the Descending Passage, since the surrounding limestone is considerably softer and easier to work.

Most of the joints between the blocks of the walls run perpendicular to the floor, with two exceptions. Firstly, those in the lower third of the corridor are vertical. Secondly, the three girdle stones that are inserted near the middle (about 10 cubits apart) presumably stabilize the tunnel.{{sfn|Maragioglio|Rinaldi|1965a|p=114-115}}

=== Well Shaft and Grotto ===
[[File:39 edgar.jpg|thumb|Grotto (left) accessed through the broken wall of the Well Shaft (right)]]
The Well Shaft (also known as the Service Shaft or Vertical Shaft) links the lower end of the Grand Gallery to the bottom of the Descending Passage, about {{Convert|50|m|ft}} further down.

It takes a winding and indirect course. The upper half goes through the nucleus masonry of the pyramid. It runs vertical at first for {{Convert|8|m|ft}}, then slightly angles southwards for about the same distance, until it hits bedrock approximately {{Convert|5.7|m|ft}} above the pyramid's base level. Another vertical section descends further; it is partially lined with masonry that has been broken through to a cavity known as the Grotto. The lower half of the Well Shaft goes through the bedrock at an angle of about 45° for {{Convert|26.5|m|ft}} before a steeper section, {{Convert|9.5|m|ft}} long, leads to its lowest point. The final section of {{Convert|2.6|m|ft}} connects it to the Descending Passage, running almost horizontally. The builders evidently had trouble aligning the lower exit.{{sfn|Haase|2004b}}{{sfn|Maragioglio|Rinaldi|1965b}}

The purpose of the shaft is commonly explained as a ventilation shaft for the Subterranean Chamber and as an escape shaft for the workers who slid the blocking stones of the Ascending Passage into place.

The Grotto is a natural limestone cave that was likely filled with sand and gravel before construction, before being hollowed out by looters. A granite block rests in it that likely originated from the portcullis that once sealed the King's Chamber.

===Queen's Chamber===
[[File:Chambre-reine-kheops.jpg|thumb|[[Axonometric]] view of the Queen's Chamber|upright=1.2]]
The Horizontal Passage links the Grand Gallery to the Queen's Chamber. Five pairs of holes at the start suggest the tunnel was once concealed with slabs that lay flush with the gallery floor. The passage is {{convert|2|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} wide and {{convert|1.17|m|ft|abbr=on}} high for most of its length, but near the chamber there is a step in the floor, after which the passage increases to {{convert|1.68|m|ft|abbr=on}} high.{{sfn|Maragioglio|Rinaldi|1965b}} Half of the west wall consists of two layers that have atypically continuous vertical joints. Dormion suggests the entrances to magazines laid here and have been filled in.{{sfn|Dormion|2004|pp=119–124}}

The Queen's Chamber is exactly halfway between the north and south faces of the pyramid. It measures {{convert|10|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} north-south, {{convert|11|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} east-west,{{sfn|Dormion|2004|p=259}} and has a pointed roof that apexes at {{convert|12|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} tall.{{sfn|Dormion|2004|p=154}} At the eastern end of the chamber is a [[Niche (architecture)|niche]] {{convert|9|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} high. The original depth of the niche was {{convert|2|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}}, but it has since been deepened by treasure hunters.

Shafts were discovered in the north and south walls of the Queen's Chamber in 1872 by British engineer [[Waynman Dixon]], who believed shafts similar to those in the King's Chamber must also exist. The shafts were not connected to the outer faces of the pyramid or the Queen's Chamber; their purpose is unknown. In one shaft Dixon discovered a ball of [[diorite]], a bronze hook of unknown purpose and a piece of cedar wood. The first two objects are now in the British Museum.<ref name="cheops.org">{{cite web|url=http://www.cheops.org/startpage/thefindings/thelowernorthshaft/lowernorth.htm|publisher=[[The Upuaut Project]]|title=Lower Northern Shaft|access-date=11 October 2010|archive-url=https://web.archive.org/web/20100729165649/http://www.cheops.org/startpage/thefindings/thelowernorthshaft/lowernorth.htm|archive-date=29 July 2010|url-status=live}}</ref> The latter was lost until 2020 when it was found at the [[University of Aberdeen]]. It has since been radiocarbon dated to 3341–3094 BC.<ref>{{cite news |title=Great Pyramid: Lost Egyptian artefact found in Aberdeen cigar box |url=https://www.bbc.com/news/uk-scotland-north-east-orkney-shetland-55315623 |work=BBC News |date=16 December 2020}}</ref> The northern shaft's angle of ascent fluctuates and at one point turns 45 degrees to avoid the Great Gallery. The southern shaft is perpendicular to the pyramid's slope.<ref name="cheops.org" />

The shafts in the Queen's Chamber were explored in 1993 by the German engineer Rudolf Gantenbrink using a crawler robot he designed, ''[[Upuaut 2]]''. After a climb of {{Convert|65|m|ft|abbr=on}},<ref>{{cite news|url=http://www.foxnews.com/scitech/2011/12/12/will-great-pyramids-secret-doors-be-opened/?test=faces |work=Fox News |title=Will the Great Pyramid's Secret Doors Be Opened? |date=12 December 2011 |url-status=dead |archive-url=https://web.archive.org/web/20120212091739/http://www.foxnews.com/scitech/2011/12/12/will-great-pyramids-secret-doors-be-opened/?test=faces |archive-date=12 February 2012 }}</ref> he discovered that one of the shafts was blocked by a limestone "door" with two eroded copper "handles". The [[National Geographic Society]] created a similar robot, which, in September 2002, drilled a small hole in the southern door only to find another stone slab behind it.<ref>{{cite web|last=Gupton|first=Nancy|date=4 April 2003|title=Ancient Egyptian Chambers Explored|url=http://news.nationalgeographic.com/news/2002/09/0910_020913_egypt_1.html|url-status=dead|archive-url=https://web.archive.org/web/20080803042156/http://news.nationalgeographic.com/news/2002/09/0910_020913_egypt_1.html|archive-date=3 August 2008|access-date=11 August 2008|publisher=[[National Geographic Society|National Geographic]]}}</ref> The northern passage, which was difficult to navigate because of its twists and turns, was also found to be blocked by a slab.<ref>{{cite web|url=http://news.nationalgeographic.com/news/2002/09/0923_020923_egypt.html|publisher=[[National Geographic Society|National Geographic]]|title=Third "Door" Found in Great Pyramid|date=23 September 2002|access-date=11 August 2008|archive-url=https://web.archive.org/web/20080727013900/http://news.nationalgeographic.com/news/2002/09/0923_020923_egypt.html|archive-date=27 July 2008|url-status=dead}}</ref>

Research continued in 2011 with the [[Djedi Project]], which used a fibre-optic "[[Fiberscope|micro snake camera]]" that could see around corners. With this, they were able to penetrate the first door of the southern shaft through the hole drilled in 2002, and view all the sides of the small chamber behind it. They discovered hieroglyphic characters written in red paint. Egyptian mathematics researcher Luca Miatello stated that the markings read "121" – the length of the shaft in cubits.<ref>{{cite news |url=https://www.nbcnews.com/id/wbna43314221 |title=Mystery of pyramid hieroglyphs: It all adds up |work=NBC News |last=Lorenzi |first=Rossella |date=7 June 2011 |access-date=1 July 2021 }}</ref> The Djedi team were also able to scrutinize the inside of the two copper "handles" embedded in the door, which they now believe to be for decorative purposes. They additionally found the reverse side of the "door" to be finished and polished, which suggests that it was not put there just to block the shaft from debris, but rather for a more specific reason.<ref>{{cite news |url=https://www.newscientist.com/article/mg21028144.500-first-images-from-great-pyramids-chamber-of-secrets.html |title=First images from Great Pyramid's chamber of secrets |date=25 May 2011 |publisher=Reed Business Information |work=New Scientist |access-date=25 December 2012 |archive-url=https://web.archive.org/web/20130106163531/http://www.newscientist.com/article/mg21028144.500-first-images-from-great-pyramids-chamber-of-secrets.html |archive-date=6 January 2013 |url-status=live }}</ref>

===Grand Gallery===
[[File:Grande-galerie.jpg|thumb|Grand Gallery (with modern walkway up the middle)]]
The Grand Gallery continues the slope of the Ascending Passage towards the King's Chamber, extending from the 23rd to the 48th [[course (architecture)|course]] (of stones), a rise of {{convert|21|m|ft}}. It has been praised as a "truly spectacular example of stonemasonry".<ref name="Smith 2018">{{cite book|first=Craig B.|last=Smith|title=How the Great Pyramid Was Built|publisher=Smithsonian Institution|year=2018|isbn=9781588346261|url=https://books.google.com/books?id=NYBKDwAAQBAJ}}</ref> It is {{convert|8.6|m|ft}} high and {{convert|46.68|m|ft}} long. Its walls are made out of polished limestone.{{sfn|Edwards|1986|pp=|p=93}} The base is {{convert|4|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} wide, but after two courses – at a height of {{convert|2.29|m|ft}} – the blocks of stone in the walls are [[corbel]]led inwards by {{convert|6-10|cm|in}} on each side.{{sfn|Maragioglio|Rinaldi|1965b}}

There are seven of these steps, so, at the top, the Grand Gallery is only {{convert|2|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} wide. It is roofed by slabs of stone laid at a slightly steeper angle than the floor so that each stone fits into a slot cut into the top of the gallery, like the teeth of a [[Ratchet (device)|ratchet]]. The purpose was to have each block supported by the wall of the Gallery, rather than resting on the block beneath it, in order to prevent cumulative pressure.{{sfnp|Kingsland|1932|p=[https://books.google.com/books?id=OieJ8015ODEC&pg=PA71 71]}}

At the upper end of the Gallery, on the eastern wall, is a hole near the roof that opens into a short tunnel by which access can be gained to the lowest of the relieving chambers.

The floor of the Grand Gallery has a shelf or step on either side, {{convert|1|royal cubit|cm+in|1|bit (|)|abbr=on|disp=x}} wide, leaving a lower ramp {{convert|2|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} wide between them. There are 56 slots on the shelves, with 28 on each side. On each wall, 25 niches have been cut above the slots.<ref>{{Cite journal|last=Lehner|first=Mark|date=1998|title=Niches, Slots, Grooves and Stains: Internal Frameworks in the Khufu Pyramid?|url=https://www.academia.edu/36645718|journal=STATIONEN: Beiträge zur Kulturgeschichte Ägyptens|pages=101–114}}</ref> The purpose of these slots is not known, but the central gutter in the floor of the Gallery, which is the same width as the Ascending Passage, has led to speculation that the blocking stones were stored in the Grand Gallery and the slots held wooden beams to restrain them from sliding down the passage.{{sfn|Lehner|1997|p=[https://archive.org/details/completepyramids00lehn/page/113 113]}} [[Jean-Pierre Houdin]] theorized that they held a timber frame that was used in combination with a trolley to pull the heavy granite blocks up the pyramid.

At the top of the gallery, there is a step onto a small horizontal platform where a tunnel leads through the Antechamber, once blocked by portcullis stones, into the King's Chamber.

===The Big Void===
[[File:East-West cut view of the Great Pyramid and front view of the North face Chevron area.png|thumb|upright=1.8|East-West cut view of the Great Pyramid and front view of the North face Chevron area. a Subterranean chamber, b queen's chamber, c grand gallery, d king's chamber, e descending corridor, f ascending corridor, g al-Ma'mun corridor, h north face Chevron area, i ScanPyramids Big Void with horizontal hypothesis (red hatching) and inclined hypothesis (green hatching) as published in November 2017.<ref name="Procureur">{{cite journal |last1=Procureur |first1=Sébastien |last2=Morishima |first2=Kunihiro |last3=Kuno |first3=Mitsuaki |last4=Manabe |first4=Yuta |last5=Kitagawa |first5=Nobuko |last6=Nishio |first6=Akira |last7=Gomez |first7=Hector |title=Precise characterization of a corridor-shaped structure in Khufu's Pyramid by observation of cosmic-ray muons |journal=Nature Communications |date=2 March 2023 |volume=14 |issue=1 |pages=1144 |doi=10.1038/s41467-023-36351-0 |pmid=36864018 |pmc=9981702 |bibcode=2023NatCo..14.1144P |language=en |issn=2041-1723 |display-authors=3}}</ref>]]

In 2017, scientists from the [[ScanPyramids]] project discovered a large cavity above the Grand Gallery using [[Muon tomography#Egyptian pyramids|muon radiography]], which they called the "ScanPyramids Big Void". A research team, under the supervision of Professor Morishima Kunihiro at [[Nagoya University]], used special [[nuclear emulsion]] detectors.<ref>{{cite web |url=http://en.nagoya-u.ac.jp/research/activities/news/2017/11/Physicists-at-Nagoya-University-discover-a-huge-void-in-Giza's-Great-Pyramid.html |title=Physicists at Nagoya University discover a huge void in Giza's Great Pyramid by cosmic-ray imaging |publisher=Nagoya University |date=22 November 2017 |access-date=5 August 2021 }}</ref><ref>{{Cite web|url=http://www.aip.nagoya-u.ac.jp/en/public/nu_research/features/detail/0004136.html|title = Research of Egyptian Pyramids with Cosmic ray Imaging &#124; Features| date=29 July 2022 }}</ref> Its length is at least {{convert|30|m|ft}} and its cross-section is similar to that of the Grand Gallery. Its existence was confirmed by independent detection with three different technologies: [[nuclear emulsion]] films, [[scintillator]] [[hodoscope]]s, and [[gas detector]]s.<ref>{{cite web|url=https://news.nationalgeographic.com/2017/11/great-pyramid-giza-void-discovered-khufu-archaeology-science/|title=Mysterious Void Discovered in Egypt's Great Pyramid|date=2 November 2017 |access-date=2 November 2017|archive-url=https://web.archive.org/web/20180727141201/https://news.nationalgeographic.com/2017/11/great-pyramid-giza-void-discovered-khufu-archaeology-science/|archive-date=27 July 2018|url-status=dead}}</ref><ref>{{cite journal|title=Discovery of a big void in Khufu's Pyramid by observation of cosmic-ray muons |display-authors=4 |first1=Kunihiro|last1=Morishima |first2=Mitsuaki|last2=Kuno |first3=Akira|last3=Nishio |first4=Nobuko|last4=Kitagawa |first5=Yuta|last5=Manabe |first6=Masaki|last6=Moto |first7=Fumihiko|last7=Takasaki |first8=Hirofumi|last8=Fujii |first9=Kotaro|last9=Satoh |first10=Hideyo|last10=Kodama |first11=Kohei|last11=Hayashi |first12=Shigeru|last12=Odaka |first13=Sébastien|last13=Procureur |first14=David|last14=Attié |first15=Simon|last15=Bouteille |first16=Denis|last16=Calvet |first17=Christopher|last17=Filosa |first18=Patrick|last18=Magnier |first19=Irakli|last19=Mandjavidze |first20=Marc|last20=Riallot |first21=Benoit|last21=Marini |first22=Pierre|last22=Gable |first23=Yoshikatsu|last23=Date |first24=Makiko|last24=Sugiura |first25=Yasser|last25=Elshayeb |first26=Tamer|last26=Elnady |first27=Mustapha|last27=Ezzy |first28=Emmanuel|last28=Guerriero |first29=Vincent|last29=Steiger |first30=Nicolas|last30=Serikoff |first31=Jean-Baptiste|last31=Mouret |first32=Bernard|last32=Charlès |first33=Hany|last33=Helal |first34=Mehdi|last34=Tayoubi |author-link34=Mehdi Tayoubi |date=2 November 2017 |journal=Nature |volume=552 |issue=7685 |pages=386–390 |doi=10.1038/nature24647 |pmid=29160306 |bibcode=2017Natur.552..386M |arxiv=1711.01576|s2cid=4459597 }}</ref> The purpose of the cavity is unknown and it is not accessible. [[Zahi Hawass]] speculates it may have been a gap used in the construction of the Grand Gallery,<ref>{{cite web |url=https://abcnews.go.com/Technology/wireStory/scientists-discover-hidden-chamber-egypts-great-pyramid-50881797|title=Scientists discover hidden chamber in Egypt's Great Pyramid |work=ABC News|access-date=2 November 2017 |archive-url=https://web.archive.org/web/20171102153724/https://abcnews.go.com/Technology/wireStory/scientists-discover-hidden-chamber-egypts-great-pyramid-50881797|archive-date=2 November 2017|url-status=dead}}</ref> but the Japanese research team state that the void is completely different from previously identified construction spaces.<ref>{{cite web |title=Critics: Nothing special about big void found in Khufu Pyramid: The Asahi Shimbun |work=The Asahi Shimbun |url=http://www.asahi.com/ajw/articles/AJ201711070057.html |url-status=live |archive-url=https://web.archive.org/web/20171108030856/http://www.asahi.com/ajw/articles/AJ201711070057.html |archive-date=8 November 2017 |access-date=8 November 2017}}</ref>

To verify and pinpoint the void, a team from Kyushu University, Tohoku University, the University of Tokyo and the Chiba Institute of Technology planned to rescan the structure with a newly developed muon detector in 2020.<ref>{{cite web|url=http://theindependent.in/the-hidden-chamber-at-giza-to-be-re-scanned-and-pinpointed/|title=The Hidden Chamber at Giza to be re-scanned and pinpointed|date=15 January 2020 |access-date=15 January 2020}}</ref> Their work was delayed by the [[COVID-19 pandemic]].<ref>{{cite web |url=https://www.express.co.uk/news/world/1346220/egypt-great-pyramid-giza-discovery-hidden-chamber-scanpyramid-pharaoh-khufu-japan-spt |title=Egypt breakthrough: Great Pyramid tipped for major discovery in new 'hidden chamber' scan |work=The Express |last=Hoare |first=Callum |date=10 October 2020 |access-date=1 July 2021 }}</ref>

=== Antechamber ===
[[File:Piazzi-plate 12.jpg|thumb|A diagram of the Antechamber|upright=1.8]]
The last line of defence against intrusion was a small chamber designed to house portcullis blocking stones, called the Antechamber. It is cased almost entirely in granite and is situated between the upper end of the Grand Gallery and the King's Chamber. Three slots for portcullis stones line the east and west wall of the chamber. Each of them is topped with a semi-circular groove for a log, around which ropes could be spanned.

The granite portcullis stones were approximately {{convert|1|royal cubit|cm+in|1|bit (|)|abbr=on|disp=x}} thick and were lowered into position by ropes, which were tied through four holes at the top of the blocks. A corresponding set of four vertical grooves are on the south wall of the chamber, recesses that make space for the ropes.

The Antechamber has a design flaw: the space above them can be accessed, thus all but the last block can be circumvented. This was exploited by looters who punched a hole through the ceiling of the tunnel behind, gaining access to the King's Chamber. Later on, all three portcullis stones were broken and removed. Fragments of these blocks can be found in various locations in the pyramid (the Pit Shaft, the Original Entrance, the Grotto and the recess before the Subterranean Chamber).{{sfn|Haase|2004b}}

===King's Chamber===
[[File:Kheops-chambre-roi.jpg|thumb|Axonometric view of the King's Chamber]]
The King's Chamber is the upmost of the three main chambers of the pyramid. It is faced entirely with [[granite]] and measures {{convert|20|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} east-west by {{convert|10|royal cubit|m+ft|1|bits (|)|abbr=on|disp=x}} north-south. Its flat ceiling is about 11 cubits and 5 digits ({{convert|5.8|m|ft|1|;||abbr=on|disp=x}}) above the floor, formed by nine slabs of stone weighing in total about 400 tons. All the roof beams show cracks due to the chamber having settled {{Convert|2.5–5|cm|in|abbr=on}}.{{sfn|Maragioglio|Rinaldi|1965a|p=48}}

The walls consist of five courses of blocks that are uninscribed, as was the norm for burial chambers of the 4th dynasty.{{sfn|Kanawati|2005|p=55}} The stones are precisely fitted together. The facing surfaces are dressed to varying degrees, with some displaying remains of [[lifting boss]]es not entirely cut away.{{sfn|Maragioglio|Rinaldi|1965a|p=48}} The back sides of the blocks were only roughly hewn to shape, as was usual with Egyptian hard-stone facade blocks, presumably to save work.<ref>{{Cite book|last=Lehner|url=https://www.academia.edu/36580864|title=Notes and Photographs on the West-Schoch Sphinx Hypothesis|year=1994}}</ref>{{sfn|Maragioglio|Rinaldi|1965b}}

==== Sarcophagus ====
[[File:Chambre-roi-grande-pyramide.jpg|thumb|Sarcophagus in the King's Chamber]]
The only surviving object in the King's Chamber is a [[sarcophagus]] made of a single, hollowed-out granite block. When it was rediscovered in the [[Early Middle Ages]], it was found broken open and any contents had already been removed. It is of the form common for early Egyptian sarcophagi, rectangular in shape with grooves to slide the now missing lid into place with three small holes for pegs to fix it.{{sfn|Petrie|1883|p=84}}{{sfn|Maragioglio|Rinaldi|1965a|p=50}} The coffer was not perfectly smoothed, displaying tool marks matching those of copper saws and tubular hand-drills.{{sfn|Stocks|2003}}

The internal dimensions of the sarcophagus are roughly {{Convert|198|cm|ft|abbr=on}} by {{Convert|68|cm|ft|abbr=in}}, the external {{Convert|228|cm|ft|abbr=on}} by {{Convert|98|cm|ft|abbr=on}}, with a height of {{Convert|105|cm|ft|abbr=on}}. The walls have a thickness of about {{Convert|15|cm|ft|abbr=on}}. The sarcophagus is too large to fit around the corner between the Ascending and Descending Passages, which indicates that it must have been placed in the chamber before the roof was put in place.{{sfn|Maragioglio|Rinaldi|1965a|p=52}}

==== Air shafts ====
In the north and south walls of the King's Chamber are two narrow shafts, commonly known as "air shafts". They face each other and are located approximately {{convert|0.91|m|ft|abbr=on}} above the floor, {{Convert|2.5|m|ft|abbr=on}} from the eastern wall, with a width of {{Convert|18 and 21|cm|in|abbr=on}} and a height of {{Convert|14|cm|in|abbr=on}}. Both start out horizontally for the length of the granite blocks they go through before changing to an upwards direction.{{sfn|Dormion|2004|p=296}}

The southern shaft ascends at an angle of 45° with a slight curve westwards. One ceiling stone was found to be distinctly unfinished, which [[The Upuaut Project|Gantenbrink]] called a "Monday morning block". The northern shaft changes angle several times, shifting the path to the west, perhaps to avoid the Big Void. The builders apparently had trouble calculating the right angles, resulting in parts of the shaft being narrower. Now, they both commute to the exterior. Whether they originally penetrated the outer casing is unknown.

The purpose of these shafts is not clear: they were long believed by Egyptologists to be shafts for ventilation, but this idea has now been widely abandoned in favour of the shafts serving a ritualistic purpose associated with the ascension of the king's spirit to the heavens.{{sfn|Jackson|Stamp|2002|pp=79, 104}}

The idea that the shafts point towards stars or areas of the northern and southern skies has been largely dismissed as the northern shaft follows a [[Dog-leg (stairs)|dog-leg course]] through the masonry and the southern shaft has a bend of approximately {{Convert|20|cm|in}}, indicating no intention to have them point to any celestial objects.<ref name="Upuaut">{{Cite web|last=Gantenbrink|title=The Upuaut Project|url=http://cheops.org|url-status=deviated|archive-url=https://web.archive.org/web/20200806133148/http://cheops.org/|archive-date=2020-08-06}}</ref>

In 1992, as part of the Upuaut project, a ventilation system was installed in both air shafts of the King's Chamber.<ref name="Upuaut" />

=== Relieving chambers ===
[[File:Piazzi-plate_13.jpg|thumb|Relieving chambers above the King's Chamber, [[Charles Piazzi Smyth|Smyth]] 1877]]
Above the roof of the King's Chamber are five compartments, named (from lowest upwards) "[[Nathaniel Davison|Davison]]'s Chamber", "[[Arthur Wellesley, 1st Duke of Wellington|Wellington]]'s Chamber", "[[Horatio Nelson, 1st Viscount Nelson|Nelson]]'s Chamber", "[[Arbuthnot baronets|Lady Arbuthnot]]'s Chamber", and "[[Patrick Campbell (1779–1857)|Campbell]]'s Chamber".

They were presumably intended to safeguard the King's Chamber from the possibility of the roof collapsing under the weight of stone above, hence they are referred to as "relieving chambers".

The granite blocks that divide the chambers have flat bottom sides but roughly shaped top sides, giving all five chambers an irregular floor, but a flat ceiling, with the exception of the uppermost chamber, which has a pointed limestone roof.{{sfn|Maragioglio|Rinaldi|1965a|p=24}}

Nathaniel Davison is credited with the discovery of the lowest of these chambers in 1763, although a French merchant named Maynard informed him of its existence.{{sfn|Vyse|1840b|p=180}} It can be reached through an ancient passage that originates from the top of the south wall of the Grand Gallery.{{sfn|Maragioglio|Rinaldi|1965a|p=24}} The upper four chambers were discovered in 1837 by [[Howard Vyse]] after discovering a crack in the ceiling of the first chamber. This allowed the insertion of a long reed, which, with the employment of gunpowder and boring rods, opened a tunnel upwards through the masonry.{{sfn|Vyse|1840a|p=155, 203pp}} As no access shafts existed for the upper four chambers – unlike Davison's Chamber – they were completely inaccessible until this point.

Numerous graffiti of red [[ochre]] paint were found covering the limestone walls of all four newly discovered chambers. Apart from levelling lines and indication marks for masons, multiple hieroglyphic inscriptions spell out the names of work-gangs. Those names, which were also found in other Egyptian pyramids like that of [[Pyramid of Menkaure|Menkaure]] and [[Pyramid of Sahure|Sahure]], usually included the name of the pharaoh for whom they were working.<ref>{{Cite web|title=How Ancient Egyptians Organized their Labor Force|url=http://www.aeraweb.org/wp-content/uploads/2015/01/aeragram7_1.pdf|pages=11–13|access-date=27 March 2021|archive-date=22 April 2021|archive-url=https://web.archive.org/web/20210422084726/http://www.aeraweb.org/wp-content/uploads/2015/01/aeragram7_1.pdf|url-status=dead}}</ref><ref name="Reisner1931" /> The blocks must have received the inscriptions before the chambers became inaccessible during construction. Their orientation, often sideways or upside down, and their sometimes being partially covered by blocks, seems to indicate that the stones were inscribed before being laid.{{sfn|Perring|1839|loc=Plates V–VII}}

The inscriptions, correctly deciphered only decades after discovery, read as follows:<ref name="Reisner1931" />

* "The gang, The Horus Mededuw-is-the-purifier-of-the-two-lands". Found once in relieving chamber 3. (Mededuw being Khufu's Horus name.)
* "The gang, The Horus Mededuw-is-pure" Found seven times in chamber 4.
* "The gang, Khufu-excites-love" Found once in chamber 5 (top chamber).
* "The gang, The-white-crown-of Khnumkhuwfuw-is-powerful" Found once in chambers 2 and 3, ten times in chamber 4 and twice in chamber 5. (Khnum-Khufu being Khufu's full birth name.)