[Sangetsu]

There are some nice beaches where I live (九十九里　or Kujukuri), which is about an hour from metro Tokyo. The sand is soft, and reasonably clean, and the surf is half decent as well. There are a variety of shells of many types, and sand dollars are common.

The beach is very popular with surfers, and there are a few surf shops and convenience stores (of course) located nearby. In the summer months food vendors set up tents on the sand, where you can enjoy a variety of things to eat.