Botswana's part of the Kgalagadi Transfrontier Park was formerly known as Gemsbok National Park, (28,400 square km) and lies in the extreme southwest of Botswana. The South African section was formerly known as Kalahari Gemsbok National Park and is 9,591 square kms in extent. There is no physical barrier between the two countries within the park. This allows wildlife to move freely and for many years there has been informal co-operation between the two authorities. This co-operation was formalized by the creation of the "Kgalagadi Transfrontier Park" on 12th May 2000 and the two former parks are now managed as a single entity, whilst still recognizing the territorial integrity of each country. On the Botswana side, the park can be divided into three areas of focus as far as tourists are concerned - the Two Rivers section, the Wilderness Trail and the Mabuasehube section. Tourists entering from the Botswana side may travel around the South African part of the park at no extra cost and without any immigration formalities. Tourists wishing to leave the park into South Africa will find that there are immigration facilities in Two Rivers/Twee Rivieren Camping facilities:Two Rivers, which faces the Twee Rivieren Rest Camp on the South African side of the border, has a camping ground with hot and cold showers and flush toilets. From Two Rivers visitors join the border road up the Nossob Valley, which is jointly used by South Africa and Botswana. Some 25 kilometres up this road on the Botswana side is the Rooiputs public camping ground, with rustic showers, pit latrines and shade shelters. For those visitors wishing to get away from the more frequently used areas, a further camping ground is situated on the Botswana side some 223 kilometres up the Nossob Valley road turning off at a place called Grootbrak. A short distance further, past a water trough, lies the Polentswa camping ground; just before which is the grave of a German diamond prospector whose remains were found after his vehicle broke down in 1958. Polentswa has a pleasant view and a good resident population of wildlife, and has the same type of rustic facilities as Rooiputs, though you need to bring all your own water.