After climbing through soft sand for almost an hour we arrived at the crest of Dune 45 just in time to see the sun rise over the rim of Tsauchab valley. Standing high above the desert floor we watched as the intense morning light caught first the summits, then the sinuous ridges and finally the vast sea of brick-red dunes that extend to the horizon in every direction. We could have been standing on the surface of an alien planet or looking at the surreal landscape of a Salvador Dali painting. The ancient dunes of Sossusvlei in the central Namib are unlike anything else on earth.
They call it the "Dune Sea" – a vast expanse of sand that the wind has whipped into giant standing waves up to 300 metres high. Dune 45, like the other dunes in the Sossusvlei area, has a gentle windward side and steep leeward side where the sand clinging to the slope is poised to slip. A sharp-crested ridge, only a few inches wide at the top, curves gracefully up from the valley to the summit. We stood there for a long time, soaking up the view before leaping onto the steep slipface and heading down. Bounding through the loose unstable sand was an exhilarating treat after our arduous climb. It took only a few minutes to return to the valley and by the next morning we knew our tracks would be gone, erased by the wind and shifting sand.
The Tsauchab River, flowing westward out of the Naukluft Mountains, penetrates 55 km into the Dune Sea. It once flowed all the way to the Atlantic Ocean but several thousand years ago its course was blocked by advancing dunes. An ephemeral lake, Sossuvlei, formed behind the dam but only during periods of exceptional rain does any water cover the sun-baked clay of its bed. Even at Dune 45, 20 km upstream from Sossuvlei, there is no sign of water. The dusty gravel flats on the broad valley bottom are baked hard by months of drought. Even after heavy rain in the Naukluft Mountains surface water rarely reaches this far west. But groundwater, flowing through the sand below the surface sustains a slender oasis of trees and shrubs. Lines of living acacia and camel-thorn trees flourish above the present underground water courses while the desiccated skeletons of their predecessors, some 5,000 years old, still stand over abandoned channels.
Dune 45, as its name implies, is 45 km downstream from the park office and campsite at Sesriem. We set up camp there the day before our early-morning trip to the dunes
Protected from the drifting sand by a circular rock wall and from the sun by the spreading canopy of an old camel-thorn tree our Sesriem campsite came with a fresh-water tap, a braae (BBQ) pit, and a stunning view across the desert to the Naukluft Mountains. After setting up the tents we drove to nearby Sesriem Canyon, a narrow gorge cut into the bedrock millions of years ago by the Tsauchab River. A trail leads down into the cleft where a standing pool of clear water is all that remains of the once mighty river. Looking straight up we can see the rim of the canyon 30m above us. This is where early ox-cart drivers lowered buckets to draw water to the surface. It took six leather reins, "sesriem", tied together to reach the pool.