The Heidentor (Heathens' Gate) is situated about 900 metres south of Carnuntum's civilian city and was presumably erected during the reign of Emperor Constantius II (351–361 AD). The Heidentor is a so-called quadrifrons, a monument on four pillars with two intersecting passageways. The Heidentor was shaped like a cube with each side about 14.5 metres long. The massive plinth in the middle, which blocks the passageways, indicates that it was a triumphal monument. A larger-than-life statue of the emperor probably stood on the plinth, which is about 4.3 metres high.
 

Heidentorgasse, 2404 Petronell-Carnuntum