It is one of the world's largest dams, built on the Nile River in southern Egypt. It creates hydroelectric power and helps irrigate Egyptian farmland. Name this dam.

This massive structure on the Nile River is the Aswan High Dam, an engineering marvel located near the city of Aswan in southern Egypt. Its construction was a pivotal moment for the nation, designed to achieve the two primary goals mentioned in the clue: controlling the river's unpredictable annual floods to support year-round agriculture and harnessing its immense power to generate hydroelectricity for Egypt's growing cities and industries.

Completed in 1970, the dam's construction created one of the world's largest artificial lakes, Lake Nasser. The creation of this vast reservoir had a monumental side effect, as its rising waters threatened to submerge dozens of ancient Egyptian temples and historical sites. In an unprecedented international campaign led by UNESCO, the most famous of these monuments, the great (Review) temples of Abu Simbel, were painstakingly cut into enormous blocks, moved to higher ground, and meticulously reassembled, saving them for future generations. The dam forever changed Egypt's relationship with the Nile, ending millennia of flood-and-famine cycles.