Editing Great Pyramid of Giza (section)

=== 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.