Beach of San Sebastian de la Gomera

I come to this beach a lot, so I know every inch of it. You can swim all year, unless the sea is dirty (but this rarely happens). Very few people - I'm usually alone on the beach. The water is cold, but not freezing, and I don't like the fact that the sand is black. This in the town centre, facing the marina, so you see all the ships swarming around. The water is comfortable and still.