Our only stop in Botswana (after a 5 hour hold-up at the border and 12 hours of driving) was at Nata, to visit the Makgadikgadi salt pan. When we visited, the pans were dry with only a few birds and wildebeest, but there are more animals when it rains and they become wet and grassy.
Looks endless, but somewhere over there is the Kalahari Desert.
Bonus elephant on the side of the road! The highway cuts across a national park so you can spot animals when you drive through.