The main river that flows through Cairo, Egypt, is the Nile River. Known as the longest river in the world, the Nile has been an essential lifeline for Egyptian civilization for thousands of years. The river provides water for irrigation, supporting agriculture in an otherwise arid landscape. Additionally, the Nile plays a pivotal role in the region's culture, history, and economy. Many ancient Egyptian monuments, including the famous pyramids, are positioned along its banks, showcasing the river’s historical significance in shaping Egypt's rich heritage.