The estuary at Noia's feet is one of the four great Galician rías — long inlets carved by the sea into the granite coastline, sheltered from the Atlantic swell, and extraordinarily productive. The mussel and oyster rafts that float on the water are a common sight; this is one of the most productive shellfish areas in Europe, and the molluscs eaten in Santiago de Compostela restaurants 35 km away were almost certainly grown here.
The ría is best seen from the waterfront promenade, where the light on the water changes dramatically through the day. In summer, windsurfers and kayakers make use of the steady afternoon breeze that funnels up the estuary. Local boat trips run from the harbour and cover the working mussel-farming operations in the outer ría.