Pietra Castle is built on a huge boulder detached from Cengio Rosso. It is located in a strategic location which marked the long border between the Italian Tyrolean territories, Bishopric of Trent and Republic of Venice. When the Venetians tried to go to the north, between the15th and 16th century , they were stopped by the Principality and the Austrians with important pitched battles that took place near the castle.
Its rooms are decorated in a Gothic style. Worth of mentioning is the 'Hall of Justice', strictly gothic atmosphere illuminated by windows with a particular form in Guelph and adorned with frescoes from the 15th century.
The castle is restored and today privately owned and inhabited.References:
The Amphitheatre of the Three Gauls was part of the federal sanctuary of the three Gauls dedicated to the cult of Rome and Augustus celebrated by the 60 Gallic tribes when they gathered at Lugdunum (Lyon). The amphitheatre was built at the foot of the La Croix-Rousse hill at what was then the confluence of the Rhône and Saône.
Excavations have revealed a basement of three elliptical walls linked by cross-walls and a channel surrounding the oval central arena. The arena was slightly sloped, with the building"s south part supported by a now-vanished vault. The arena"s dimensions are 67,6m by 42m. This phase of the amphitheatre housed games which accompanied the imperial cult, with its low capacity (1,800 seats) being enough for delegations from the 60 Gallic tribes.
The amphitheatre was expanded at the start of the 2nd century. Two galleries were added around the old amphitheatre, raising its width from 25 metres to 105 metres and its capacity to about 20,000 seats. In so doing it made it a building open to the whole population of Lugdunum and its environs.