The Bianca C, a 600-foot cruise liner nicknamed the Titanic of the Caribbean, sunk in 1961 and remains upright beneath the water. Divers who visit the wreck often spot eagle rays, moray eels, nurse sharks, barracuda and even schools of Atlantic spadefish.
Photo courtesy of Grenada Tourism Authority

Cozumel's Santa Rosa Reef is part of the Great Mesoamerican Reef, the second largest coral reef on the planet. A popular spot for sighting sea turtles, the reef also provides a home for sponges, French grunts, groupers, turtles, angelfish and even the occasional green moray eel.
Photo courtesy of Roberto LIebig / Flickr

Sometimes called the Galapagos of Puerto Rico, Mona Island boasts an impressive biodiversity both above and below the surface of the water (some of the clearest in Puerto Rico). Horizontal visibility often exceeds 200 feet – the perfect conditions for spotting turtles, marlins, whales, dolphins and some of the island's 60 reef-dwelling species.
Photo courtesy of NOAA Restoration Center, Erik Zobrist

Just west of Saba's Fort Bay harbor lies Tent Reef, a rock ledge 13 feet below the surface that gets progressively deeper until it turns into a sheer wall. By day divers might spot large snapper or colorful sponges, but it's also a popular night dive site thanks to visits from turtles, octopus and spiny lobster.
Photo courtesy of Saba Tourism

One of Bonaire's most popular shore dives gets its name from the 64 steps leading down to the entry point that purportedly feel like 1000 on the way back up. Just offshore, clusters of star coral have formed pagoda-like formations found in few other places on the planet, where divers might spot hawksbill turtles, manta rays and even the occasional whale shark.
Photo courtesy of Paul Asman and Jill Lenoble / Flickr

Utila has no shortage of stellar dive sites, but one of the best is CJ's Drop Off, a steep wall plunging 140 feet below the surface. With endless ocean to one side and a colorful reef to the other, divers can spot sea turtles, moray eels, barracudas and spotted eagle rays.
Photo courtesy of iStock / Matt_Potenski

Mary's Place, one of Roatan's most famous dive sites, provides a habitat for all sorts of marine critters – including coral, sponge and lots of seahorses.
Photo courtesy of iStock / BrianLasenby

One of the world's top wreck dives, the Hilma Hooker lies 60 to 99 feet below the surface of the water near a double reef system in Bonaire. Accessible by boat or from shore, the site showcases a relatively young artificial reef, giving divers an idea of just how long it takes coral to recover from damage.
Photo courtesy of Patrick Briggs / Flickr

It'll take at least two dives to fully explore the wreck of the Rhone in the British Virgin Islands, but it's well worth the effort. Descending down toward the ghostly ship, divers can see schools of Sennets, grunts and barracuda. The hull is covered in orange cup corals.
Photo courtesy of iStock photo

The Grand Turk Wall sits not far from the island's west coast. A brief boat ride brings divers to one of the best wall dives in the tropical Atlantic, where visibility often exceeds 100 feet and the reef "architecture" features overhangs, tunnels, archways and pinnacles. 
Photo courtesy of stokes rx / Flickr