Lepsius Number One
This mudbrick structure located at Abu Rawash was thought by the Lepsius expedition to be the northernmost pyramid in Egypt and so was given the name Lepsius Number One. However, the jury is still out on whether it is in fact a pyramid and which pharaoh should be credited with its construction.
It is considered by some to be one of the small step pyramids (known as the seven small pyramids) which stretch from Seila to Elephantine. Yet, unlike these pyramids Lepsius Number One does have an internal substructure and so could well have been intended as a tomb.
The Egyptologist Swelim has attributed it to Huni of third dynasty of the Old Kingdom, for whom no other burial pyramid has so far been located. He considered that it was a step pyramid built from mudbrick on top of a core or rock. This is disputed by another Egyptologist, Verner, who notes that unlike other pyramids it sits at the edge of the flood plain rather than at a safe elevation. He also notes that there are a number of rock cut tombs cut into the rock that Swelim considers to be the core of the pyramid and these are thought to date to the fifth and sixth dynasties of the Old Kingdom. The only way these later tombs could have been cut into the rock after the pyramid was built would be for it already to have collapsed which he considered unlikely.
The pyramid was built by stacking layers of mudbrick over a core or rock. By the modern era most of the mudbrick had been stripped away, but it is estimated that it was between one hundred and one hundred and fifty meters high with a base length of around two hundred and fifteen meters making it comparable in size to the unfinished pyramid at Zawiyet el Aryan. A sloping corridor was cut into the rock which led down to a small square burial chamber.