The so called Palace Ruins, adjacent to the site of Carnuntum’s forum, are situated to the west of Schloss Petronell. The ruins are, in fact, the remains of a huge public baths which was lavishly equipped and magnificently decorated with vibrant marble walls and mosaic covered floors. Today the remains of the under floor heating systems, sewers, bathing and swimming pools, cellar rooms and large domestic offices can be seen as well as a market hall with shops and store rooms. This is one of the largest Roman bathing houses north of the Alps.