A Roman colony in Spain, founded by the Romans in 25 BC as Augusta Emerita. As the capital of Lusitania (roughly equivalent to modern Portugal), it became one of the most important towns in Iberia and was large enough to contain a garrison of 90,000 men. It prospered anew in the 7th century under the Visigoths. Roman buildings survive: theater, amphitheater (both built by Agrippa), circus, temples, aqueducts, and a Roman bridge of 64 arches. There is a temple of Diana, an arch of Trajan, aqueducts and conduits, a group of structures devoted to Mithras and other mystery cults, and a number of rich houses with colonnaded courts and mosaics (including the so-called 'Creation of the Universe'). Gold tesserae are found, and some of the sculptures, especially Roman marble portraits, are of fine quality.