Praia de Matosinhos
Also known as Praia Internacional (International beach) this is a wide beach, with plenty of space. Experienced surfers can get better waves near the rocks on the side. Generally, the waves are rideable by all surfers, regardless of their experience. Peaks works better on bigger swells. This is also a great place to start surfing and to have some surf lessons. Normally, the waves aren't too big. It works with all tides. Quite crowded, though, as it is Porto's urban beach.
The best spot is on the left, next to the jetty. On larger days, the right works on the other side of the beach. The bed is sandy with some rocks. The best swell direction is NorthWest, West, and SouthWest, and the best wind come from the East and the NorthEast