The Pyramid of Djoser, a UNESCO World Heritage Site located 20 miles south of Cairo considered the first stone pyramid ever built in Egypt, reopened to the public this month following a painstaking renovation. The project cost $6.6 million and took a total of 14 years to complete, given the three-year hiatus between 2011 and 2013 during the Egyptian revolution.
According to legend, the architect Imhotep designed and oversaw the assembly of the 197-foot-tall pyramid between 2630 and 2611 B.C.—nearly 4,700 years ago—as the first vertical tomb for the Pharaoh Djoser. Though the structure appears to be a solid mass from the outside, its interior is an almost entirely hollow network of walking paths measuring more than three miles, with the assembly of over 11.6 million cubic feet of stone and clay, according to Atlas Obscura.
The elaborate interior, however, has significantly threatened its structural integrity over time, while the foundation was nearly decimated by the 1992 Cairo earthquake. To ensure that the structure would not collapse in on itself during the renovation, airbags designed by structural engineer Peter James were placed throughout the pyramid’s most vulnerable sections. Steel rods were additionally run through the terraced steps like rebar to permanently reinforce the pyramid’s shape. These two fortification methods allowed the renovation team to restabilize the structure’s ceilings and corridors, while also adding a new lighting system and entryway for people with disabilities to provide just a few modern updates that would make the structure more widely accessible.
“We are working hard to build a new Egypt … and the restoration of our heritage is at the top of our priorities,” Egyptian Prime Minister Mostafa Madbouli told reporters during a press conference held on March 5 to celebrate the reopening, according to Business Insider. Visitors were then offered a chance to explore its narrow corridors and stairways with the guidance of archaeologists who pointed out the many extra chambers, false doorways, dead ends, and other details designed to confuse grave robbers.