Just outside the city walls at Newgate, the Roman amphitheatre is the largest ever found in Britain. It was built around 100 AD to serve the garrison of Deva Victrix — the 20th Legion's fortress that became the city of Chester — and excavations have revealed the oval arena, the surrounding seating banks, and the entrance passages through which both performers and wild animals entered.
The site is freely accessible and well interpreted with information panels. Only the northern half has been excavated; the southern half remains below the grounds of a Victorian convent. What is visible gives a convincing sense of scale: this was a substantial structure, and the city that built it was a major Roman military installation rather than a provincial backwater. The adjacent visitor centre (in the former amphitheatre museum building) provides additional context.