Experience the rich maritime history of the Great Lakes - above and below the waves - as you explore the shipwrecks of the Thunder Bay. Home to the nation’s only freshwater National Marine Sanctuary, Alpena’s 200 shipwrecks can be viewed by diving, snorkeling, kayaking, or stand up paddle boarding in the blue waters of Lake Huron. Or enjoy the view from above and schedule a glass-bottom boat tour of these magnificently preserved shipwrecks, scenic shorelines and majestic lighthouses. | Pure Mich