The Roman amphitheater of Cagliari is a building from the Roman era, located in Cagliari. The structure, built in the 2nd century AD, was half carved out of the rock, with the remainder built in local white limestone, with a facade exceeding 20m in height. It hosted fights between men and animals, gladiators and other specialized fighters recruited inside and outside Sardinia. It was also the site of public executions. It could accommodate up to 10,000 spectators, about a third of the Roman Caralis.
The amphitheatre was no longer in use starting from the 5th century AD and was subsequently used as a free stone quarry by the rulers of the area, from the Byzantines, the Republic of Pisa, the House of Aragon and others. The area was acquired by the comune of Cagliari in the 19th century and excavated under the direction of a clergyman, Giovanni Spano. It is now used for musical presentations, which required the construction of a structure whose presence has raised criticism owing to its size.