A signature experience in Negril is to go on a two-hour glass-bottom boat snorkel trip, toward the cliffside or to the nearby reef around Booby Cay. Truth be told, snorkeling isn't a must if you're not up for it—but floating on a small boat amid deep jade and turquoise waters and being able to see marine life 20 feet or more below through the glass is a memorable experience. If you do want to snorkel, the cliffside has stunning limestone formations and underwater caves, while the reef is filled with all sorts of marine life, from stingrays to barracuda. A glass-bottom boat ride shouldn't cost you more than US$20 per person. Look out for Famous Vincent's boat—the best pick—or approach one you see resting along Seven Mile Beach, across any reputable resort. The boats—including Vincent—occasionally ride along the cliffside resorts in the mornings or afternoons, looking for anyone interested in an impromptu adventure.