Known during the Middle Ages as Vayna, it used to belong to the monastery of Oia domains. In 1482 Diego de Muros, bishop of Tui, annexed it to Baiona. The medieval name seems to come from "vaíña", Galician word meaning "sheath" and also and “pod".

It stretches from Santa Marta peninsula to Chan da Lagoa Forest Park. Santa Marta was Pirate Drake's headquarters when he tried to capture Baiona. Before giving up, the smuggler profaned and burnt to the ground the chapel, which the people rebuilt later on.

However, the chapel is not the only artistic remaining. In Santa Marta you can find an area of prehistoric stone carving; five minutes walking from Chan da Lagoa and you will see the remaining walls and bridges of the medieval village called San Cosme, under reconstruction now. Besides, this is a highly rich forest-resource parish where wild horses run and graze free in A Lagoa hillsides.

Centres of population: Almirante Fontán, O Burgo, Cruceiro, Eidos, Fontes, Igrexa, Laxes, Río, San Cosme and Santa Marta.

Patroness: St. Marina and St. Marta.