The Mandraki was the military harbour and was guarded by a tower built between 1464 and 1467 by the Grand Master Zacosta at the end of the natural mole. After the siege of Rhodes in 1480 the Grand Master d'Aubusson added a bastion around the tower transforming it into a guard fortress on the sea.
The castle was built at the place of an old Byzantine church dedicated to St. Nicholas, hence the name. Since the 17th century, a lighthouse was added at the top.
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.