If your idea of a great vacation means being near the water, head to Cinque Island. No matter what you choose to do here, you're unlikely to tire of those lovely views.
You'll need to find your way to Andaman and Nicobar Islands to reach this water-surrounded land mass. If you intend to do some sightseeing after you're done, why not drop by Jolly Buoy Island? It's within reach of Cinque Island.