The surroundings of Keetmanshoop in southern Namibia are characterized by the bizarre rock formations of the 180 million years old Keetmanshoop Dolerite Complex, which is allied to the incipient break-up of the Gondwana supercontinent that united the landmassses of the southern hemisphere between 550 to 150 million years ago. Interspersed with sedimentary rocks of the Karoo Supergroup (~320 to 200 million years), which demonstrate a major climate change from glacial to subtropical, the dolerite covers an area of more than 18000 km², verging on the Kalahari sandveld. In addition, the area is known for various important fossil sites of the aquatic reptile Mesosaurus tenuidens, which - having been found both in southern Africa and South America - proves the erstwhile connection between the two continents, as well as the antediluvian-looking quiver trees that thrive in the soil derived from the weathered dolerite.