We left Fish River Canyon for the long day's drive to Sesriem - the scenery along the way was beautiful, we began to see the red sand of the Namib desert. We saw lots of sociable weaver birds' nests in the trees and on telephone poles.

We went on a walk through the desert at Sossusvlei with Franz, whose grandfather had been a bushman and taught him how to survive in the desert on wild plants and animals - he shared this knowledge with us and told us some funny stories as he guided us around the dunes. Franz explained how to navigate using the sun and the dunes - east-west winds form north-south dunes which don't move because nara plants hold them in place (these plants can grow to 100 metres tall, with most of their height buried under sand).

Franz demonstrated that black patches in the sand were actually iron - he gathered up a bunch of it with a magnet. Franz showed us the ostrich salad plant which dries up and closes when there is no water so that its seeds don't fall on arid ground; then the next time water falls on the plant it opens up and spreads its seeds - we could actually see this happening when water was dropped on the plant. He caught some little lizards which he said could be eaten raw if you were stranded in the desert (thankfully he didn't demonstrate this!). We saw a wheeling spider that rolls down the dunes and we saw a spider that builds a tunnel down into the dune in which to live and just pops out to catch prey when it hears something move overhead.

He explained that, when you are within 1km of the ocean, it is possible to dig 1m down into the sand and use the stalk of a plant as a straw to suck up water from the sand; this can then be stored in ostrich eggs for months if necessary. When there is no water, the animals eat plants for water. The acacia tree is an important plant in the desert, with roots that can grow to 50-80 metres deep.

We saw Dead Vlei - a dried up lake that looked like a car park set among the dunes! There hasn't been any water there for 1,000 years but there are still remains of trees that died 600-900 years ago (the wood is too hard for insects to eat so it has survived).

After climbing up and running down the dunes, Franz told us about the history of the bushmen and fighting that wiped them out of this area. He also told us about the marriage ritual of the tribal people - a girl's suitors have to prove their worth by killing an oryx. On the way back we saw some springbok and ostriches.

The next day we were up at 4:30am for the challenging trek up to the top of Dune 45 to watch the sunrise. There were lots of other tourists there too. It was very cold and a strange fog moved in after sunrise. After we'd run back down the dune and emptied the piles of sand out of our shoes we were delighted to discover coffee and bacon sandwiches ready at the truck