A century ago, Lake Michigan was a freshwater freeway, connecting major cities like Chicago, Milwaukee, and Wisconsin’s Green Bay. But the notorious storms of the Great Lakes region often made for a tumultuous passage. Today, the lake -- the fifth largest in the world — is home to roughly 1,500 documented shipwrecks, serving as haunting reminders of the past. Explore them this summer by jumping on board one of these unique tours.

Door County, Wisconsin

Located between Lake Michigan and the waters of Green Bay, Door County got its name from the early French explorers and Native Americans who referred to the narrow, dangerous strait between the Door Peninsula and Washington Island as Porte des Morts, which translates literally to “Door of the Dead.” The county claims more than 300 miles of shoreline, which is riddled with the skeletons of ships that date back to the mid-1800s. To explore them, try one of the clear bottom kayak shipwreck tours, like the one from Gravity Trails ($55 per person), which leads you past shipwrecks visible through the shallow waters of North Bay. For a closer look, check out the Snorkeling Adventure Shipwreck Trip offered by Lakeshore Adventures. For $60 per person, explorers can dive down to the Frank O’Connor -- a 300-foot wooden ship that sank just off the coast of Cana Island in 1919. Perhaps the most unique way to see the shipwrecks of Lake Michigan is by air. Grizzly Scenic Air Tours offer daily tours from May 1 to October 31 that give a bird's-eye view of lakeside shipwrecks along with the other colorful scenery of Door County. A 70-minute tour for three sightseers will run you just under $300 total.

Traverse City, Michigan

With beautiful beaches and an emerging food scene, Traverse City is becoming the ideal weekend getaway. But don’t be fooled by its laidback, small-town vibe; Traverse City is home to plenty of adventures -- most of which can be found on the glassy waters of Lake Michigan. Paddle Away Tours offers guided excursions by kayak to see shipwrecks and the lake’s majestic lighthouses. For a more in-depth look, the folks at Scuba North offer training and certifications for divers of all levels to be able to explore areas like the Grand Traverse Bay Underwater Preserve. Among the many ships that rest there, the most memorable is the Metropolis, a 125-foot schooner that was lost in a snowstorm in 1886 and ran aground near the Old Mission Point.

Chicago, Illinois

Although Chicago is brimming with attractions, the shipwreck tour offered by Windy City Diving is among the most interesting ways to learn about Chicago’s maritime past. More people have lost their lives off of the shores of Chicago than anywhere else on the Great Lakes. Many of those shipwrecks are entombed in shallow waters, making dive trips incredibly accessible. Windy City offers trips to area wrecks like the Thomas Hume, a lumber-hauling schooner that went missing in 1891, and the Wings of Wind, a wooden schooner that sank in 1866 following a collision on the lake. Today, the latter ship rests in only 40 feet of water and provides exceptional photo opportunities for adventure-seekers.

Milwaukee, Wisconsin

The waters off the shores of Milwaukee, Wisconsin are home to more than 10 shipwrecks. Sign up for a diving trip with Milwaukee-based Shipwreck Explorers, and you can visit wrecks ranging from wooden steamers and barges to diesel yachts and car ferries. The Prins Willem V, known as the "Willie” -- which sunk in 1954 and lies intact about 80 feet underwater -- has penetrations possible for experienced divers. For die-hard adventurers, Shipwreck Explorers also includes Expedition Dives, which reach depths of 300 feet and include a chance to discover unchartered territory alongside the crew.