Four Seasons Hualalai
The Four Seasons Hualalai resort on the Big Island boasts seven pools. The most exciting one is King's Pond, which is home to more than 3,000 tropical fish. Borrow the resort's snorkeling equipment for a better look and you'll get lost in the colorful shoals. The pool, carved out of natural lava rock, is filled with fresh and ocean water that moves with the tide.