The patrol left Sesriem early, following the river. Trenk describes the narrow course with its high, rocky banks eventually widening as they rode down its twists and turns. Huge camelthorn trees lined the banks. Many miles further, as the first high dunes began encroaching from the north, he noted that the river was heading directly westwards in a wide valley. Besides the many camelthorn trees along the river, he also noted the dead trees about 35 kilometres from Sesriem. These dead camelthorn trees are still visible when travelling to Sossusvlei, just north of the present road. With the reduction in water flow as the area became drier and drier, the river no longer pushed its life-giving waters so far onto the plain, and the young trees died from lack of water. Their remains have not disappeared, as the arid conditions are unfavourable for bacteria and the dry wood will take many hundreds of years to decompose and disappear. Dead Pan, named for the stark skeletons of camelthorn trees that sporadically punctuate its cracked white clay floor, has been host to these graphic ghosts for over 500 years and will probably present the same eerie scenario for another few centuries.
Trenk and his troopers found pools in the river, which provided much-needed sustenance to their horses. On the evening of 11 February, they camped in the Tsauchab riverbed, waiting for the moon to rise before continuing their journey during the cool night hours. The horses were grazing when animals, possibly hyaenas, frightened them and they took off. Although the men looked for their scattered mounts by moonlight, they could only continue their journey later the next morning after walking a long way to find them. Trenk reports seeing gemsbok and ostrich, but makes no mention of springbok. The trees became fewer as they rode down the river, eventually disappearing altogether.
On the evening of 12 February, they reached a thick stand of trees, most likely a little north of the present 2×4 car park. After crossing some low dunes, Trenk and his patrol reached the end of the Tsauchab River valley, finding big camelthorn trees and many !nara bushes. The !nara is a remarkable desert-adapted plant that has no leaves but produces an abundance of melon-sized fruits that are an essential source of food and liquid for many desert-dwelling animals. Gemsbok, springbok, jackal, hyaena, rodents and birds depend on the !nara to survive in the harsh desert environment. On several !nara plants Trenk noted ostrich wings put over the fruit, which he assumed had been placed there by local people, possibly the San/Bushmen, to act as scarecrows to keep animals away from the moist, nutritious fruits with their sweet yellow juice, which they possibly used as a substitute for water.
The troopers inspected the area, but found no signs of water, or of the reputed Bushman Paradise. Despite the pools in the river, the floodwaters had not been sufficient to reach the pan at Sossusvlei. Because of the lack of water and grazing for their horses, they left at midnight and rode back to Sesriem. In his official report, accompanied by a map and published in the Deutsches Kolonialblatt 1910 (Volume 20, No 17), Trenk notes that at Sossusvlei the Tsauchab River disappears into the dunes. He may have been the first white man to see the place now known as Sossusvlei. Certainly, his was the first recorded visit to this now world-famous tourist draw card surrounded by the towering red dunes of the Namib Desert.