The interior of the Matrouh Governorate is part of Egypt's
Western Desert, including the
Siwa Oasis, in antiquity known for its shrine to
Amun. In the centre of the Governorate is the
Qattara Depression, descending to 133 metres below sea level. Marsa Matrouh is the ancient
Paraitónion,
Latin Paraetonium. It was the westernmost city of the
Ptolemaic Kingdom in the
Hellenistic period. The city of
Apis, some 18 km to the west of Paraetonium, marked the boundary to Libycus
nome, and the
Halfaya Pass (at
Sallum) marked the boundary to
Marmarica proper. Matrouh Governorate contains many historical sites related to
World War II. The latter include
el Alamein, which comprises cemeteries of fallen soldiers from
Axis and
Allied forces. An estimated 16 million mines, planted by the Europeans during the world wars and called "
devil's gardens", still hinder the development of most of the governorate, and are constantly being removed. ==Population==