3 Best Sights in Vienna Woods, Lake Neusiedler, and the Danube River, Austria

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.

Situated in the heart of Hainburg, these castle ruins (easily approached on foot) are equally appealing for the castle's long and illustrious history and the lovely views from the top. During the 11th century, Hainburg was a fortified town on the far eastern front of the Holy Roman Empire, and in 1252, Przemsyl Ottaker, the king of Bohemia, married Duchess Margarethe of Austria here, a union designed to considerably expand his kingdom. The castle had been built shortly before that with part of the ransom received from the capture of King Richard the Lionheart in Dürnstein. The Schloss was attacked many times, most severely by the 1683 Turkish invasion, which also took the lives of 8,000 residents, nearly the entire community. Each summer the town hosts "Burgspiele Hainburg," where open-air plays (often Shakespeare) are performed in German on the castle grounds.