


The length of this depression ranges between 5, 55 and 60 km, while its average width is 10 km, and its deepest point reaches 24 meters below sea level. The depression is the smallest depression in the Egyptian Western Desert, with an area of about 500 km2. Therefore, it is true that it is a depression and not a valley, because the region is a closed depression that has a beginning and an end, and it has no source, estuary or tributaries, so the launch of the word "Wadi" on the depression is not topographically correct. The Wadi contains 12 lakes, the total surface area of which is 10 km square and their average depth is only 2 m. The color of these lakes is reddish blue because its water is saturated with the Natron salt. Natron valley is first attested in the story of the Eloquent Peasant, and it is mentioned among the list of seven oases in the Temple of Edfu.

In Ptolemaic times it constituted part of the Nitrite nome ( Ancient Greek: Νιτριώτης νομός). It was also known in Coptic as Mountain of Salt ( Coptic: ⲡⲧⲱⲟⲩ ⲙⲡϩⲙⲟⲩ). The importance of the Natrun valley dates back to the Pharaonic era, as the ancient Egyptian and the Libyans fought there many battles. And this ended up with the Egyptians overcoming them and annexed the eastern side of the desert, which still belongs to Egypt. Then, Wadi al-Natrun became an administrative part of the country in the Pharaonic era, but there is no information about its history during their reign, and the latest writings on the wars between the libu and the Egyptians indicate that the last of them was in 1170 BC during the reign of Ramesses III. Īs for the religious significance of Wadi al-Natrun, there are many discoveries that indicate that this area was considered sacred as early as year 2000 BC at the very least. Among these discoveries is a bust of black granite dating back to the era of the Seventeenth Dynasty of the Pharaohs, and there is also a granite gate and stones from the lintel of a door bearing cartridges for King Amenemhat I, in a place called the backbone. The alkali lakes of the Natron Valley provided the Ancient Egyptians with the sodium bicarbonate used in mummification and in Egyptian faience, and later by the Romans as a flux for glass making. The Egyptian Salt and Soda Company Railway was built at the end of the 19th century as a 33 miles (54 km) long narrow gauge railway with a gauge of 750 mm, which attracted the first tourists to the wadi. The desolate region became one of Christianity's most sacred areas.
