Estuary of the Ulla Nature · Catoira, Caldas, Pontevedra Image of Catoira, not of the place itself. Head of the ría of Arousa, on the final stretch of the river, where fresh water mixes with the tide and the channel widens into rush beds, sandbanks and marsh. It is a passage area for lampreys and shad and for migratory birds, with traditional shellfishing on foot, and the natural setting against which the ruins of the Torres do Oeste stand out. Photo: Luis Miguel Bugallo Sánchez [http://commons.wikimedia.org/wiki/User:Lmbuga http://gl.wikipedia.org/wiki/User:Lmbuga (CC BY-SA 3.0) What to see and do in Catoira