From tropical islands to mountain lakes and jagged coastlines to sandy beaches, water tends to make any getaway instantly more exotic. There are a lot of fantastic hotels out there boasting turquoise ocean views and H2O proximity. Some bungalows even put you directly over the sea, letting you take a quick dip or feed the fish at a moment's notice. But for a truly once-in-a-lifetime aquatic experience, some resorts take it to entirely new depths. Read on for five underwater resorts that will put you face to face with the incredible world under the sea.