For someone who usually visits small, town beaches, South Beach seems immense! It is part of a 3-mile stretch of sand on the south side of Martha's Vineyard. We arrived on bikes, so there was no fee to enter the beach for us; we just locked up the bikes on a convenient bike rack at the entrance. The sand is picture-perfect clean, so it is great for a day of lounging on the beach. The water has that clean azure-gray ocean color. There are no rocks or big pebbles, so getting into the water is painless. The waves on our visit were not too large at all. The sea floor falls off fairly quickly--15 feet into the water and I could not stand any longer. This is good for swimming around, but not so good for body surfing or boarding, because the waves don't break unless they are huge.
Overall a great experience!
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.