Because of its rounded form, the unexcavated amphitheatre was known to locals as 'King Arthur's Round Table', but there is no known connection.
An initial investigation in 1909 showed the potential for a full-scale excavation of the structure, which began in 1926 and was supervised by Victor Erle Nash-Williams.
This revealed, among other things, that the amphitheatre had been built around 80.
This (Period I) building was destroyed by fire in the early-second century, and the second (Period II) building erected c.
AD138 was destroyed around sixty years later c.196/7.
It was rebuilt for the third and last time during the campaigns of Severus and Caracalla in Britain c.197–211.
The Period III building finally fell into disuse around the middle of the fourth century at the same time that the Caerleon fortress was evacuated.
The latest coin from this site is that of Valens (AD364–378).

The arena is oval in shape, with eight entrances, and the stadium is thought to have had a capacity of around six thousand spectators, and apart from the usual gladiatorial entertainments, it was probably used for parades, displays and exercises by the garrison of the fortress.
Because of its rounded form, the unexcavated amphitheatre was known to locals as 'King Arthur's Round Table', but there is no known connection. An initial investigation in 1909 showed the potential for a full-scale excavation of the structure, which began in 1926 and was supervised by Victor Erle Nash-Williams. This revealed, among other things, that the amphitheatre had been built around 80. This (Period I) building was destroyed by fire in the early-second century, and the second (Period II) building erected c.AD138 was destroyed around sixty years later c.196/7. It was rebuilt for the third and last time during the campaigns of Severus and Caracalla in Britain c.197–211. The Period III building finally fell into disuse around the middle of the fourth century at the same time that the Caerleon fortress was evacuated. The latest coin from this site is that of Valens (AD364–378).
The arena is oval in shape, with eight entrances, and the stadium is thought to have had a capacity of around six thousand spectators, and apart from the usual gladiatorial entertainments, it was probably used for parades, displays and exercises by the garrison of the fortress.
Isca Augusta