Maui Ocean CenterLargest tropical aquarium in the Western Hemisphere, a 750,000-gallon Open Ocean tank, and the only 360° humpback whale dome in Hawaii

Maui Ocean Center opened in 1998 in Maʻalaea Harbor as the first aquarium in the world dedicated entirely to a single tropical island ecosystem. Every exhibit features only Hawaiian marine species — no Atlantic angelfish, no aquarium-bred surgeonfish from Indonesia, no captive-born dolphins. The aquarium's research and conservation arm is one of three accredited turtle rehabilitation centers in the state; rescued green sea turtles recover here before being released back to Hawaiian waters.

The headline exhibit is the Open Ocean tank — 750,000 gallons in a single oval, 35 feet at the deepest point, with a 240-foot acrylic walk-through tunnel that puts visitors directly beneath sandbar sharks, white-tip reef sharks, eagle rays, and a resident green sea turtle named Hina. Above the tunnel, an open viewing platform lets divers (with special booking) drop into the tank itself for a $400 cage-free shark dive — Hawaii's only public-access dive of its kind.

Beyond the tunnel: a Living Reef tank with 60+ Hawaiian fish species, a Hawaiian Cultural Galleries gallery covering pre-contact navigation and fishing techniques, and the Humpback Sphere — a 360° immersive dome opened in 2021 that puts visitors inside Hawaiian waters during the December–April humpback whale migration. The dome runs every 30 minutes; sit in the center seats for the best surround. Plan two and a half to three hours; the on-site Seascape Restaurant has a harbor-view lanai and the best mahimahi sandwich on the island.