Bulla Regia is a Roman archaeological site in northwestern Tunisia, remarkable for one thing: its underground villas. The wealthy Roman residents of this city built their houses with a full storey below ground to escape the fierce North African summer heat, and the subterranean rooms have preserved some of the finest floor mosaics in all of Roman Africa.
You can walk down into the underground rooms of the House of Amphitrite and the House of the Hunt and stand on mosaic floors that are still vivid after nearly two thousand years. The Forum and Temples at ground level complete the picture of a prosperous provincial Roman city. The site is far less visited than Dougga or Carthage, and on a quiet day you may have the ruins largely to yourself. Bulla Regia is about 150 kilometres west of Tunis, near the town of Jendouba, and is easily combined with a visit to Dougga in a single day trip.