In ancient times, the First Cataract at Aswan marked the southern frontier of Egypt. Beyond lay the land of Nubia, which stretched along the river Nile from the First Cataract southwards for about 250 kilometres (155 mi). This region, known as Lower (northern Egyptian) Nubia, functioned as a buffer zone between the two power centres of Egypt and Kush, the latter extending farther to the south to the Sixth Cataract in modern Sudan.
This is a companion discussion topic for the original content at https://www.worldhistory.org/article/1963/sailing-on-lake-nasser-towards-abu-simbel/.