Substructure of the Pyramid at Abu Roash
The pyramid has a 49 meter long open trench (left: from above, right: looking down) to the interior shaft (21x9x~20 m) with the grave chamber. This was an abandoned way of working from the third dynasty that was taken up by Djedefre and shortly after by pharaoh Bikka (see him). The total volume of stone cut out can be estimated to around 6.000 cubic metres. 