In the Florida Keys, while you may still technically be in the US, there is a distinct Caribbean twist, and once you're lying on the beach with a rum cocktail in hand, you'd be forgiven for forgetting that you're even connected to the mainland at all. This hundred-mile thread of islands has a selection of idyllic and secluded luxury hotels that will make you want to get on a plane tomorrow. These are our top picks on where you can stay to enjoy the turquoise oceans and top-quality diving and snorkelling of the Florida Keys.