Distance travelled through from Arriondas:16 a 20 Km

The confluence of the river Sella with the Cantabrian Sea takes place in Ribadesella forming thus its estuary or estuary. The estuary is respected as zone of special protection for the birds (ZEPA) and place of common interest (LIC).

The estuary presents this spectacular aspect since the nearby mounts that surround Ribadesella.

The island of the Boticaria is formed in half of the estuary to scarce meters of the confluence of the Sella with the Cantabrian Sea, when the tide is drop is possible to agree her, although with difficulty, due to that the floor is slippery.