The Tsau ǁKhaeb (Sperrgebiet) National Park, formerly known as Sperrgebiet (German, meaning "Prohibited Area"; also known as Diamond Area 1) is a diamond mining area in southwestern Namibia, in the Namib Desert. It spans the Atlantic Ocean-facing coast from Oranjemund on the border with South Africa, to around north of Lüderitz, a distance of north. It extends to around inland, and its total area of , makes up three percent of Namibia's land mass. However, mining only takes place in five percent of the Sperrgebiet, with most of the area acting as a buffer zone. Members of the public are banned from entering most of the area, despite the creation of a national park there in 2004.
In September 1908, the German government created the Sperrgebiet in its colony of German South West Africa, giving sole rights for mining to the Deutsche Diamantengesellschaft ("German Diamond Company"). In 1915, during World War I, South African forces led by General Jan Smuts and Louis Botha, the South African Prime Minister, invaded the country. The South Africans defeated the Germans, taking control of modern-day Namibia, including the Sperrgebiet. The owner of the mine, De Beers, had total control of the area until the 1990s, when the Namibian government purchased a fifty-percent stake. They formed a joint partnership called the Namdeb Diamond Corporation.
The mining area close to Bogenfels is called "Pocket Beaches" which is one of Namdeb's northern coastal mines. The Sperrgebiet has a diverse range of flora and fauna, due to little human intervention in the area for 100 years. Forty percent of the landscape is desert, thirty percent is grassland, and twenty-eight percent is rocky. Roter Kamm, an impact crater in the southern Namib Desert within the Sperrgebiet, has a diameter of . The area includes the Tsaus Mountains, Mount Aurus, Mount Heioab, Mount Höchster, the Klinghardt Mountains and the permanent water spring Kaukausib. The highest point of the Sperrgebiet is .