Citânia de Briteiros, Archaeological site in Briteiros São Salvador, Portugal.

Citânia de Briteiros is an archaeological site on Monte de São Romão with the remains of a Celtic settlement. The hillfort contains paved streets, stone walls, and the outlines of about 150 round houses that formed a fortified community.

The settlement was founded in the 2nd century BCE and remained inhabited until the 2nd century CE. The transition to Roman times gradually altered the site's structure, though Celtic foundations remained visible beneath later changes.

The site's name, Citânia, comes from the Latin civitas, meaning a fortified town. Visitors can see the reconstructed dwellings that Francisco Martins Sarmento built in the 1870s, and the Pedra Formosa, a carved stone slab from one of the bathhouses, now kept in the Martins Sarmento Society museum in Guimarães.

The site sits on a hillside and is easy to explore, with clear paths and building outlines visible throughout. Wear comfortable shoes as the terrain is uneven and some sections slope steeply.

The visible ruins date mostly from the last two centuries BCE, yet the hill was used long before: Atlantic Bronze Age rock engravings covered Monte de São Romão, and many engraved boulders were cut up to build the ramparts and family compounds. Excavations also found a medieval chapel and graveyard on the acropolis.