Meidum Pyramid

A three-stepped stone tower rising out of a huge mound of its own rubble, alone in the fields south of Cairo. It looks like nothing else in Egypt — locals call it el-haram el-kaddab, "the false pyramid" — and it is one of the most instructive ruins in the country.

What you are looking at is the inner core of a pyramid whose outer skin came away. The debris heaped around the base is that skin. You can walk into the burial chamber down a descending passage, and the corbelled roof inside is worth the awkward climb.

Also here

The mastaba of Nefermaat and Itet stands nearby. It produced the Meidum Geese — a painted frieze of six geese so precisely observed that the species are identifiable, and one of the acknowledged masterpieces of Old Kingdom art. The original is in the Egyptian Museum in Cairo.

The pyramid was begun as a step pyramid, probably under Huni, and then converted by Sneferu into a true smooth-sided pyramid by packing the steps and adding an outer casing. It was the first attempt at that shape anywhere.

What went wrong

It failed. The casing was built on a foundation of sand rather than bedrock and laid in courses that sloped outward, so it had nothing holding it in. At some point the whole outer mantle slid off and piled up around the base, leaving the stepped core standing.

Whether that happened during construction or centuries later is still argued. What is not argued is the consequence: Sneferu moved to Dahshur and tried again, twice — the Bent Pyramid, where the angle was reduced mid-build, and then the Red Pyramid, which worked.

Why it matters

Meidum is the first entry in a sequence you can still follow on the ground. One reign, three pyramids, one visible failure and two corrections — and at the end of it, the confidence to build at Giza. Most visitors see only the finished product; this is where the process started going wrong and being fixed.