Situated on the left bank of the Navia Estuary, Coaña is a hilltop settlement (4th Century BC) surrounded by walls and accessed from the south. The main defensive structure is located precisely in the south and consists of a wide ditch dug into the slaty subsoil finished off by a wall. Inside, the settlement is divided into several sectors.
It has a diamond shape in which the following areas can be clearly distinguished:
- The acropolis. A triangular enclosure surrounded by a wall. It was not used for housing. Access to this area was protected by a square tower.
- The northern sector.The residential sector spreads out beneath the north wall of the acropolis, mostly consisting of circular huts. Some of them are accessed via a hall or corridor. The walls are made of slate with rounded corners.
- The holy precinct.Inside the residential sector near the gate to the acropolis, there are two groups of buildings associated with channelling water and a pool, a granite vessel called a "bath", which suggests that it was used for bathing or rustic saunas.
