Carnuntum
The remains of the important Roman legionary fortress and civil town of Carnuntum, which once numbered 55,000 inhabitants, extend about five kilometers (three miles) along the Danube from the tiny village of Petronell to the next town of Bad Deutsch-Altenburg. The recent discovery here of an ancient school of gladiators delighted archaeologists and significantly raised Carnuntum's stature, and rightfully so. Visitors can tour the grounds, which include two amphitheaters (the first one seating 8,000) and the foundations of former residences, reconstructed baths, and trading centers—some with mosaic floors. The ruins are quite spread out, with the impressive remains of a Roman arch, the Heidentor (Pagans' Gate), a 15-minute pleasant walk from the main excavations in Petronell. You can experience what Roman life was like circa AD 380 in the elegantly furnished Villa Urbana. Many of the excavated finds are housed at the Museum Carnuntinum at Bad Deutsch-Altenburg. The star of the collection is a carving of Mithras killing a bull. Guided tours in English are available in July and August at noon; otherwise they are in German only.