Suwarrow is an uninhabited atoll in the Cook Islands. Good beaches are available. But this is not a real beach destination, since it's a National Park inhabited by rangers during the dry season. So this is rather a spot for ecotourism, accessible by private boats only. However, occasional cruises from Rarotonga are also available. You'll get paradise views, as well as good snorkeling. Shore and seabed: sand, stones.