Sex on the beach sounds hot... until you actually DO IT. Then you find out its gritty and painful and you're better-off waiting until you get back to the hotel. But seriously, do NOT let me stop you. Fuck on the beach and decide for yourself.

Or, if you're into "proper prior planning", bring some silicone-based lube (which won't wash off in water) and try doing it IN THE WATER! Just sayin...