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.
References:Celje Castle was once the largest fortification on Slovenian territory. The first fortified building on the site (a Romanesque palace) was built in the first half of the 13th century by the Counts of Heunburg from Carinthia on the stony outcrop on the western side of the ridge where the castle stands. It had five sides, or four plus the southern side, which was a natural defence. The first written records of the castle date back to between 1125 and 1137; it was probably built by Count Gunter. In the western section of the castle, there was a building with several floors. Remains of the walls of this palatium have survived. In the eastern section, there was an enclosed courtyard with large water reservoirs. The eastern wall, which protects the castle from its most exposed side, was around three metres thicker than the rest of the curtain wall. The wall was topped with a parapet and protected walkway.