Situated on the left bank of the Navia Estuary, Castro de 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 three areas can be clearly distinguished. The acropolis is a triangular enclosure surrounded by a wall, not used for housing. Access to this area was protected by a square tower. The northern 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.
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.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.