These are the Roman ruins of Dougga in Tunisia. They are some of the best preserved Roman ruins in Africa, largely because they are in a very rural area so people weren't hauling away stones for new constructions like they would if it was near a city. Unfortunately, because it is such a rural area transportation isn't very good and we could only do about an hour of exploring because the last louage (shared minibus) of the day back to Tunis left in the early afternoon.