A sunken crater that sits like a crescent moon fallen from the sky, almost midway between Maui and the uninhabited island of Kahoolawe, Molokini stands like a scoop against the tide. This offshore site is very popular, thanks to astounding visibility (you can often peer down 100 ft. or more) and an abundance of marine life, from manta rays to clouds of yellow butterflyfish. On its concave side, Molokini serves as a natural sanctuary and preserve for tropical fish; the back “wall” is an exciting place to snorkel or dive as well. Molokini is accessible only by boat, and snorkelers commute here daily in a fleet of dive boats. See “Boating,” above, for outfitters that can take you here. Expect crowds, unless you arrive early via a sunrise cruise or speedy raft.