While the core was under construction, a corridor was left open leading into the shaft where the grave chamber was built separately and later covered by leftover stone blocks and debris. This construction strategy is clearly visible in later unfinished pyramids, in particular the Pyramid of Neferefre. This technique also reflects the older style from the Third Dynasty seemingly coming back into fashion after being temporarily abandoned by the builders of the five great pyramids at Dahshur and Giza during the Fourth Dynasty.