Veii (also Veius, ) was, in ancient times, an important Etruscan city NNW of Rome, Italy; its site lies in Isola Farnese, a village of Municipio XX, an administrative subdivision of the comune of Rome in the Province of Rome. Many sites associated with Veii, which were in the city-state of Veii, are also located in Formello, another comune of the Province of Rome, immediately to the north. Formello is named after the drainage channels first created by the Veians.
Veii was the richest city of the Etruscan League, on the southern border of Etruria. It was alternately at war and in alliance with Rome for over 300 years. It eventually fell to the Roman general Camillus's army in 396 BC. Veii continued to be occupied after its capture by the Romans;
In the "Parco di Veio" adjacent to Isola Farnese, there are remnants of an apparent temple. Also tumuli and tombs have been found cut into the rock. Tombs were cut into tuff but tumuli were not. The most famous is the Grotta Campana, uncovered in 1843, a chamber tomb with the oldest known Etruscan frescoes. There are additionally long tunnels leading into the mound of the city, which may corroborate Livy's account of the Roman victory in the Battle of Veii.