Egyptian construction project of the 1960s, completed with assistance from Soviet Russia (5,3)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
aswan dam
(Other definitions for aswan dam that I've seen before include "Nile construction of 1902" , "Egypt's lake district" , "Huge structure in Africa" , "Egyptian water barrier" , "massive barrier" .)