Embraced by some of northern California’s most beautiful shoreline, Monterey Bay National Marine Sanctuary is one of the largest protected marine areas in the world. Millions of visitors are drawn to the otters, harbor seals, and birds that splash along its beaches—but it is the sanctuary’s blue expanse of water that teems with an unsurpassed explosion of life.

Twenty-six species of marine mammals live in the sanctuary. Besides the seals and otters, bottlenose dolphins and two species of porpoises live there year-round. And each year a variety of sea lions, dolphins, and whales drop by. All told, the sanctuary is home to 26 species of marine mammals, 94 species of seabirds, 345 species of fish, 4 species of turtles, 31 types of invertebrates, and 450 species of large marine algae.

Venture above and below the waters of the Monterey Bay sanctuary in this interactive feature, a companion to the Sustainable Seas Expeditions site. “Fly” through the bay’s awesome undersea canyon—twice as deep as the Grand Canyon—and board a submersible exploration vehicle for a dive at the edge of a kelp forest. Come face to face with the sanctuary’s creatures and gain a new understanding of the need to preserve and protect the wilderness that lies below the ocean waves.