44 years ago today, on November 27, 1981 (November 2, 1981 in the lunar calendar), a huge underground river valley was discovered under the Egyptian desert. Egypt's huge underground river valley On November 27, 1981, a huge underground river valley was discovered under the Egyptian desert. On November 27, 1981, during the second test flight of the US space shuttle "Colombia", a huge underground river valley submerged under the desert in southwestern Egypt was discovered through a telemetry system. This discovery aroused great interest among Egyptian scientists. This discovery was made when it rained only once in more than 40 years in this desert area. The signal from the space shuttle telemetry system could penetrate a dry sand layer 4.6 meters deep. According to this discovery, this desert, which is currently uninhabited and the driest in the world, was once an area with fertile land, smooth winds and rains, and prosperous people and livestock 20,000 to 50,000 years ago. There were some huge rivers there. Connecting Egypt and Sudan. Underground in this desert, there is an underground river valley 25 times larger than the Nile Basin, with a width of 25 to 30 kilometers. As the years passed, deserts gradually covered these rivers and river valleys. Some scientists believe that life of ancient Egyptians began in this desert area and later migrated to the Nile River Basin. Scientists also believe that there are rich groundwater and rare metals under this desert, which will be of great significance to Egypt's economic development. The traditional view is that Egyptian groundwater absorbs Sudanese groundwater, but this new discovery reverses this assumption. Sudan's groundwater is replenished from Egyptian groundwater.