Sossusvlei

Sossusvlei, the large pan (flat-bottom depression) of salt and clay, typically white in color, that is surrounded by massive orange-red sand dunes in the southern region of the Namib, a coastal desert in Namibia. Sossusvlei is located in the Namib Sand Sea, a region of dune fields that covers about 13,000 square miles (34,000 square km). Sossusvlei and the Namib Sand Sea lie within the boundaries of Namibia’s Namib-Naukluft National Park, the largest national park in Africa and one of the largest in the world. International tourists come to view the stunning natural beauty of the dunes, which, at up to 1,065 feet (325 meters) in height, are some of the world’s largest sand dunes. The region is one of Namibia’s most famous natural features, and the landscape has appeared in commercials and films.

Sossusvlei was formed over the course of millennia through a combination of wind action and the flow of the ephemeral Tsauchab River, which originates in the Naukluft Mountains to the east. It is thought that the Tsauchab once flowed to the coast and emptied into the Atlantic Ocean, about 35 miles (55 km) to the west of Sossusvlei. Today, however, the Tsauchab terminates at Sossusvlei, where, over time, the river became blocked and dammed by the formation of sand dunes. The dunes that surround Sossusvlei were formed by wind-blown sediment from dry riverbeds—including the Tsauchab riverbed—as well as areas in Africa’s interior and from the coast. Over tens of millions of years, winds have blown this sediment thousands of miles into the dunes of the Namib Sand Sea. The orangish-reddish color of the dunes comes from the coating of iron oxide on the grains of sand in the dunes.

Namibia’s climate is hot and arid, with little rainfall, and most years Sossusvlei is completely dry and white with salt. In the rare years with heavy rainfall, the Tsauchab River flows all the way to Sossusvlei and the salt-and-clay pan—also known as a playa or a vlei—becomes a lake surrounded by plants and visited by animals. Wildlife in the area includes gemsboks (species of oryx), ostriches, jackals, kudus, springboks, and several species of birds, reptiles, and arthropods.

Many of the dunes near Sossusvlei are star dunes. From the ground, star dunes resemble pyramids, but when viewed from above, long “arms” that radiate from the center of the dunes are visible, similar to the form of a starfish. This dune shape occurs when winds regularly blow from several directions. Near Sossusvlei, the winds come mainly from the south, but there are also winds that blow from the east along the Tsauchab valley and warm, dry winter winds from the northeast. The dunes are constantly shaped and reshaped by the wind.

The Namib Sand Sea is a fog desert; much of the area’s moisture comes from fog, and many of the endemic animals found there get the water they need from fog. UNESCO, which named the region a World Heritage site in 2013, noted:

“Namib Sand Sea is the only coastal desert in the world that includes extensive dune fields influenced by fog....Fog is the primary source of water in the site, accounting for a unique environment in which endemic invertebrates, reptiles and mammals adapt to an ever-changing variety of microhabitats and ecological niches.”