A Caribbean coral reef in Boston? You’ll find it at the New England Aquarium, as part of the aptly named Giant Ocean Tank, which contains 200,000 gallons of water and is swimming with sharks, sea turtles, barracuda, and hundreds of other reef fish. While you can meet a family of harbor seals right outside the front door of the aquarium, it’s well worth your time to head inside to explore the exhibits that focus on habitats from the Amazon rain forest to the Gulf of Maine. The aquarium also boasts an IMAX theater and touch tanks, and if you want to encounter local marine life in their natural environment, you can join one of Boston Harbor Cruises’ whale-watching tours, which depart from the Central Wharf daily between March and November.