Lucca's Piazza dell'Anfiteatro preserves the outline of a Roman amphitheatre within a ring of inhabited buildings. Ancient Luca stood at a strategic meeting of roads and river routes in northern Tuscany, and Roman colonization encouraged a regular street plan and substantial public architecture. The amphitheatre was built outside the original urban core during the imperial period, probably in the first or second century CE. Its scale reflected the ambitions of a prosperous regional community connected with the wider political and economic networks of Roman Italy.

The original building enclosed an elliptical arena with tiers of seating supported by a system of arches, passages, and radial walls. Spectators entered through controlled approaches, while performers and attendants used spaces beneath or beside the seating. Gladiatorial contests and animal spectacles turned the arena into a public stage for civic generosity and imperial culture. Surviving masonry is most readily visible on the outside of the present housing ring, where ancient arches and reused structural elements reveal the framework concealed behind later façades and domestic interiors.

When Roman spectacles ceased, the amphitheatre became a convenient source of stone and a ready-made enclosure for new uses. Medieval buildings occupied its walls and vaults, and the arena filled with houses, workshops, storage, and other structures. The curve survived because property boundaries and load-bearing walls followed the ancient shell. This gradual adaptation protected the overall footprint even as it destroyed much of the original architecture. Lucca's later urban development absorbed the site, turning what had been a venue outside the ancient core into a dense neighborhood.

In the nineteenth century, architect Lorenzo Nottolini reshaped the area into a market square. Beginning in 1830, his project removed buildings from the former arena and regularized the surrounding façades while retaining the elliptical enclosure. New approaches improved circulation, and the resulting space served commercial life within the modern city. The square therefore represents both Roman survival and a deliberate later intervention. Its harmonious appearance was not simply uncovered intact beneath medieval occupation but created through selective demolition, repair, and architectural design.

Today shops, cafés, apartments, and public activity occupy the buildings around the open piazza. Conservation involves maintaining ordinary inhabited property as well as identifying and protecting ancient masonry within it. Moisture, structural alterations, tourism, and the demands of modern services can affect fabric concealed behind familiar façades. The square is significant because it makes urban continuity visible through shape: a Roman arena became a medieval neighborhood and then a nineteenth-century market, with each phase retaining the ellipse while changing almost everything about how people used the space.