The river that is being described is the Nile river.
It is generally considered the longest river in the world with an estimated length of almost 6.700 km. It flows north from remote sources in the mountains of Ethiopía and Central Africa and discharges into the Mediterranean Sea.
The Nile played an important role in the cultural history and creation of Egypt because permanent settlements gradually rose along the river and this was the beginning of the Egyptian civilization.
Neighboring lands were extremely fertile due to periodic flooding and annual inundations and the Egyptians were able to cultivate wheat and other crops, providing food for the population.