Carnuntum was a Roman Legionary Fortress and also headquarters of the Pannonian fleet from 50 AD. After the 1st century it was capital of the Pannonia Superior province. It also became a large city of 50,000 inhabitants. In Roman times Carnuntum had a history as a major trading centre for amber, brought from the north to traders who sold it in Italy; the main arm of the Amber Road crossed the Danube at Carnuntum. Its impressive remains are situated on the Danube in Lower Austria in the Carnuntum Archaeological Park extending over an area of 10 km² near today's villages of Petronell-Carnuntum and Bad Deutsch-Altenburg.
The remains of the civilian city extend around the village Petronell-Carnuntum. There are several places to see in the city: Roman city quarter in the open-air museum, palace ruins, amphitheatre, and Heidentor.
Some way outside the city was a large amphitheatre, which had room for about 15,000 spectators. A plate with an inscription found at the site claims that this building was the 4th largest amphitheatre in the whole Roman Empire.
Between 354 AD and 361 AD, Heidentor, a huge triumphal monument was erected next to the camp and city. Contemporary reports suggest that Emperor Constantius II had it built to commemorate his victories. When the remains of Carnuntum disappeared after the Migration Period the monument remained as an isolated building in a natural landscape and led Medieval people to believe it was the tomb of a pagan giant. Hence, they called it Heidentor (pagan gate).
References:The historical centre of Briançon is a strongly fortified town, built by Vauban to defend the region from Austrians in the 17th century. Its streets are very steep and narrow, though picturesque. Briançon lies at the foot of the descent from the Col de Montgenèvre, giving access to Turin, so a great number of other fortifications have been constructed on the surrounding heights, especially towards the east.
The Savoyards made two raids into French territory in 1691 and 1692. As a result, Vauban was dispatched to inspect the frontier defences, which had been ill-equiped to deal with the attack from Savoy. He returned to the area in 1700 to check on the progress that had been made since his first visit. When Vauban visited Briançon, work on the defences had already started under a local engineer, Monsieur d"Angrogne in 1692.