Editing Silbury Hill (section)

==Investigations==
[[File:Silbury 1.jpg|thumb|Silbury Hill seen from the south east]]
[[File:Silbury Hill, England.jpg|thumb|Silbury Hill, modern artistic recreation of its construction {{Circa|2350 BC}}]]
[[File:Silbury Hill, as seen from West Kennet Hill.jpg|thumb|Silbury Hill, as viewed from the nearby hill on which [[West Kennet Long Barrow]] is located]]

===17th, 18th, and 19th centuries===
The site was first illustrated by [[John Aubrey|Aubrey]], the 17th-century antiquarian, whose notes, in the form of his ''Monumenta Britannica'', were published between 1680–1682. Later, [[William Stukeley|Stukeley]] wrote that a skeleton and bridle had been discovered during tree planting on the summit in 1723.{{efn|
It is probable that the skeleton and bridle unearthed in 1723 was from a later, secondary burial.
}} In October&nbsp;1776, a team of [[Mining in Cornwall and Devon|Cornish miners]] overseen by [[Hugh Percy, 2nd Duke of Northumberland|the Duke of Northumberland]] and Colonel Edward Drax sank a vertical shaft from the top.<ref>
{{cite news
 |last=Hinman |first=Niki
 |date=2 February 2010
 |title=Long-lost theory on Silbury Hill is uncovered
 |place = Swindon, UK
 |newspaper = [[Gazette and Herald|The Wiltshire Gazette and Herald]]
 |url=https://www.gazetteandherald.co.uk/news/4884791.long-lost-theory-on-silbury-hill-is-uncovered/
 |access-date=2021-07-13
}}
</ref> Brian Edwards argues that Drax and his friends—all members of [[Anna, Lady Miller|Mrs. Millers]]' poetry set in Batheaston—were interested in Silbury Hill, because they thought it paralleled the Greek legends of Apollo killing [[Python (mythology)|Python]], the monstrous snake that lived in the Caves of Parnassus.<ref>
{{cite journal
 |last = Edwards  |first = Brian
 |date = Winter–Spring 2013
 |title = Imagining 'Silbury and Parnassus the same', Edward Drax and the Batheaston vase adventure
 |journal = The Regional Historian
 |issue = 26 |pages = 21–16
}}
</ref> In 1849, a tunnel was dug horizontally from the edge into the centre. In 1867, the [[Wiltshire Archaeological and Natural History Society]] excavated the east side of the hill to see if traces of the Roman road were underneath it. No traces were found, and later excavations south of the hill located the road in fields to the south, making a pronounced swerve to avoid the base of the hill. This was conclusive proof that the hill was there before the road—but the hill provided an alignment sight-line for the road.<ref>
{{cite book
 |title = Silbury Hill
 |publisher = BBC Publications
 |year = 1969
}} — Refers to the excavations for the [[BBC TV]] programme dealing with the new 1968–1969 excavations for [[BBC2]] TV programmes about the hill
</ref>

===20th century===
[[Flinders Petrie]] investigated the hill after the First World War. From 1968 to 1970 professor [[Richard J. C. Atkinson]] undertook work at Silbury which was broadcast on [[BBC Television]]. This excavation revealed most of the environmental evidence about the site, including the remains of winged ants which indicate that Silbury was begun in an August. Atkinson dug numerous trenches at the site and reopened the 1849 tunnel, where he found material suggesting a Neolithic date, although none of his [[radiocarbon dating|radiocarbon date]]s are considered reliable by modern standards. He argued that the hill was constructed in steps, each tier being filled in with packed chalk and then smoothed off or weathered into a slope. Atkinson reported the [[carbon 14 dating|C-14 date]] for the base layer of turf and decayed material indicated a corrected date for the commencement of Silbury was close to {{nobr|2750 {{sc|BCE}}.}}<ref>
{{cite book
 |first = Aubrey |last = Burl
 |year = 1979
 |title = Prehistoric Avebury
 |publisher = Yale University Press
 |page = 129
}}
</ref>

===21st century===
After heavy rains in May&nbsp;2002, a collapse of the 1776 excavation shaft caused a hole to form in the top of the hill. [[English Heritage]] undertook a [[reflection seismology|seismic survey]] of the hill to identify the damage caused by earlier excavations and determine the hill's stability. Repairs were undertaken, but the site remained closed to the public. As part of this remedial work, English Heritage, with help from AC Archaeology, excavated two further small trenches at the summit. Neil Adam from AC Archaeology made the important discovery of an [[antler]] fragment, the first from a secure [[archaeological context]] at the site. A radiocarbon date of {{circa| {{nobr|2490–2340 {{sc|BCE}}}} }} dates the second phase of the mound convincingly to the Late Neolithic.<ref name=BA70>
{{cite magazine
 |last=Field |first=David
 |date=May 2003
 |title=Great sites: Silbury Hill
 |magazine = British Archaeology magazine
 |publisher = Council for British Archaeology
 |place = York, UK
 |issue = 70
 |issn=1357-4442
 |url=http://www.britarch.ac.uk/ba/ba70/feat2.shtml
}}
</ref>

In March&nbsp;2007, English Heritage announced that a [[Roman Britain|Roman]] village had been found at the foot of Silbury Hill. It contained regularly laid out streets and houses.<ref>
{{cite news
 |title = Silbury Hill reveals Roman settlement
 |date = 2007-03-10
 |agency = [[Reuters]]
 |website = reuters.com
 |url=https://www.reuters.com/article/uk-britain-monument-idUKL1053491320070310
 |access-date=2021-07-13
 |language=en
}}
</ref>

In May 2007, contractors [[Skanska]], under the overall direction of English Heritage,<ref name=eh>
{{cite web
 |title = Silbury Hill Conservation Project, Wiltshire
 |year = 2008
 |website = [[English Heritage]]
 |url = http://www.english-heritage.org.uk/caring/conservation-projects/silbury-hill/
 |url-status = dead
 |archive-url = https://web.archive.org/web/20130120122945/http://www.english-heritage.org.uk/caring/conservation-projects/silbury-hill/
 |archive-date = 20 January 2013
}}
</ref> began a major programme of stabilisation, filling the tunnels and shafts from previous investigations with hundreds of tonnes of chalk. At the same time a new archaeological survey was conducted using modern equipment and techniques.<ref>
{{cite news
 |title = Tunnel open again at Silbury hill
 |date = 2007-05-11
 |website = [[BBC News]]
 |url = http://news.bbc.co.uk/2/hi/uk_news/england/wiltshire/6645367.stm
 |access-date = 2021-07-13
}}
</ref> The work finished in early 2008; a "significant" new understanding of the monument's construction and history had been obtained.<ref>
{{cite magazine
 |last = Pitts |first = Mike
 |date = 6 June 2008
 |title = Silbury is safe
 |magazine = British Archaeology magazine
 |issue = 101  |page = 8
 |publisher = Council for British Archaeology
 |place = York, UK
 |issn = 1357-4442
}}
</ref>

In 2010, letters written by Edward Drax concerning the 1776 excavation were found in the British Library. He describes a "perpendicular cavity" {{convert|40|ft|adj=off}} deep and {{convert|6|in|cm}} wide. As wood fragments—thought to be oak—have been found, it has been suggested that this may have held an oak tree or a "[[totem]] pole".<ref>
{{cite news
 |title = Silbury Hill 'built around pole'
 |date = 2010-02-03
 |website = [[BBC News]]
 |url = http://news.bbc.co.uk/2/hi/uk_news/england/wiltshire/8495004.stm
 |access-date = 2021-07-13
}}
</ref>

[[File:Silbury hill.jpg|thumb|Silbury Hill 3D model]]
[[File:Silbury Hill Profile A 1.jpg|thumb|Silbury Hill 3D model]]
[[File:Silbury hill.webm|thumb|Silbury Hill 3D model video]]

===Comparable sites===
[[File:Prehistoric Silbury Hill, Wiltshire.JPG|thumb|right|Silbury Hill after heavy rain]]
Following the 2007–2008 works, archaeologists investigated whether Silbury Hill was the only such mound built by the people of the time, or if there might be other comparable mounds that have not been recognised as prehistoric. A strong candidate was felt to be the [[Marlborough Mound]], in the grounds of [[Marlborough College]], {{convert|8.3|km|miles}} east of Silbury Hill, further down the [[River Kennet]]. The mound is {{convert|18|m|ft}} high, less than half the height of Silbury. There are archaeological and documentary indications that the Marlborough Mound had been used for medieval fortifications known as [[Marlborough Castle]], and it had been identified as a Norman [[Motte-and-bailey castle|motte]]. A team of archaeologists, led by Jim Leary, analysed core samples from two 10&nbsp;cm diameter boreholes. Charcoal from immediately below the mound was from around {{nobr|2500 {{sc|BCE}},}} making it a close contemporary of Silbury.<ref name=leary1>
{{cite journal
 |last1 = Leary    |first1 = Jim
 |last2 = Marshall |first2 = Peter
 |date = December 2012
 |title = The giants of Wessex: The chronology of the three largest mounds in Wiltshire, UK
 |journal = [[Antiquity (journal)|Antiquity]]
 |volume = 86 |issue = 334 |pages =
 |issn = 0003-598X
 |url=http://www.antiquity.ac.uk/projgall/leary334/
 |access-date=12 August 2016 }}
</ref>

Another contender, but which had been all but levelled in the 19th&nbsp;century, was at [[Marden Henge]], {{convert|10|km|miles}} south of Silbury. Known as Hatfield Barrow, a surviving fragment of what may have been a 15&nbsp;m high mound also gave construction dates to the {{nobr|mid-3rd millennium {{sc|BCE}}.}}<ref name="leary1" />

The Round Mound Project to investigate other likely mounds began in 2015, and from 154&nbsp;potential sites across England, 20 were selected for core sampling and detailed surveying. By late 2017, 14 had produced results confirming that they were built immediately after the [[Norman invasion of 1066]]. Three were shown to be later medieval mounds and one was from Saxon times, so may be a burial mound. Only one, [[Skipsea Castle]] mound in East Yorkshire, was found to be prehistoric, but dating to {{nobr|800–400 {{sc|BCE}},}} during the [[British Iron Age]]. On the basis of this survey, it would appear that Neolithic mound-building was restricted to the upper Kennet and Avon valleys, and that nothing extant elsewhere in Britain comes close as a comparison to Silbury Hill.<ref name=leary2>
{{cite journal
 |first1 = Jim    |last1 = Leary
 |first2 = Elaine |last2 = Jamieson
 |first3 = Phil   |last3 = Stastney
 |date = March 2018
 |title = Normal for Normans? Exploring the large round mounds of England
 |journal=[[Current Archaeology]]
 |issue = 337 |pages = 18–24
 |issn = 0011-3212
 |url=https://www.archaeology.co.uk/articles/normal-normans-exploring-large-round-mounds-england.htm
 |url-access=limited |access-date=4 March 2018 }}
</ref>

===Artifacts===
Few prehistoric [[Artifact (archaeology)|artifact]]s have been found on Silbury Hill: at its core there is only clay, flints, turf, moss, topsoil, gravel, freshwater shells, mistletoe, oak, hazel, [[Sarsen|sarsen stones]], ox bones, and antler tines. Roman and [[Middle Ages|medieval]] items have been found on and around the site since the nineteenth century.{{Citation needed|date=June 2022}}