Study of the archaeological evidence suggests that earlier interpretations of the development of the royal tombs of the 25th Egyptian Dynasty at the site of El-Kurru in the Sudan should be revised. Contrary to Reisner’s original theory, that their development followed a similar sequence to the pyramids in Egypt, which included an intermediate mastaba stage, the monuments in the Sudan underwent a more abrupt change to the pyramidal form, signaling the advent of their new empire.