The Arrimal lagoons are surrounded by calcareous wells. The Lagoa Pequena (Small Lagoon), located by Arrimal, gets the water from its own basin. Both lagoons are surrounded by pyrenean oaks, a species that is rare in this region.

Located by the sea, this dune surrounded lagoon is th biggest set of lakes to the north of Sines. It is about 5 km long and 1 km wide and spreads inland along old rice fields. The red-crested pochard, the mallard, the coots and the black-necked grebes are some of the species that live in this habitat. Ideal for sailing or spending a day at th beach.

The dam of Fagilde.

The Sizandro River flows to the ocean, by the Praia Azul (Blue Beach), after 35 km.

When you get to the mouth, the big Ria de Aveiro, the Vouga River spreads in fairways (being that some get into the city itself). Behind are 150 km, since the Serra da Lapa, and several contributions to thicken the flow, the last of them quite close to the mouth – the Águeda River.

A wide estuary, with several areas of benches and swamps. It is separated from the sea by the peninsula of Tróia and it is composed by two main regions: the central bay of Setúbal and Marateca and the Alcácer channel. The inner part of the estuary is surrounded by rice fields and cane fields and the outter part is densely populated and industrialized.

The river flows to the southwest. It has its mouth to the south of Castelo de Neiva, in the district of Viana do Castelo.

The Minho river has its mouth in Caminha, by the Camarido Woods. There is a small river beach in a protected area. Just a few metres away, there is the Park of the Camarido Woods.

The approximate 175 km of the Lima river (67 km in Portugal) end in the beautiful city of Viana do Castelo, with the Santa Luzia belvedere well on the top. Its mouth is also a boating area of extreme importance in the North of Portugal and in Galicia. We can find two recreational docks (one upstream and another downstream of the train bridge). Further ahead, the commercial port, the fishing port and the shipyards mark the transition to the Atlantic Ocean with a wharf.

When it comes to its mouth, in lovely Esposende, the Cávado river forms almost a tidal stream. It leaves 130 km behind, since the Larouco Hill. In the ocean, by the mouth, there is a group of rocks named Cavalos de Fão (Horses of Fão). By the mouth of the Cávado river there is an old lighthouse and its house.