Japan’s Summer is very, very hot. Make sure to use lots of sunscreen, bring a shirt, water and something to protect your head. If you visit Kamakura Beach outside the weekend, it will not be crowded at all. The sea water is warm and you can find huge shells. Rental shops and beach huts are open for business during the swimming season. There are also convenient facilities such as showers and toilets. Definitely worth a visit!
Kamakura Beach is a 15 minute walk from Kamakura Station, you can use google maps or follow the signs. For more information, visit Kamakura’s official website (in English): http://en.kamakura-info.jp/