Now a small town in the middle of nowhere (well, at the edge of the desert), El Jem, the ancient Roman town of Thysdrus, was formerly a crossroads of the caravan trade and a very wealthy town, as you can see in its amazing coliseum, which is probably the finest anywhere - including the one in Rome. You can really see how the Roman Empire had an influence even on remote parts of the Empire, and how the locals wanted to outdo Rome. The place is not far from the touristy coast, so a trip from there is not complicated and no doubt worth the effort.