The red iron in the dunes is emphasised at sunrise by the low angle of the rising sun. The patterns in the sand are emphasised.
The dunes are either side of the dry Tsauchab River. Stretching 1,600 kilometres (1,000 miles) in length, but averaging a width of only 110 kilometres (70 miles), the Namib Desert is home to the highest sand dunes in the world up to 340 metres high. Namib Naukluft National Park, at Sussovlei, Namibia, Africa.