The Roman Amphitheatre of Cagliari is an ancient Roman amphitheatre, located in the city of Cagliari. The structure, built in the 2nd century AD, was half carved in the rock, while the rest was built in local white limestone, with a façade surpassing 20 m in height. It housed fights between men and animals, of gladiators and other specialized fighters recruited in and outside Sardinia. It was also the seat of public executions. It could house up to 10,000 spectators, some one 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.