Ghost towns litter the Keweenaw, faded testament to the boom-and-bust days of copper. The ruins of old mines and stamping plants (facilities that separated copper from rock) line M-26 between Hancock and Calumet. The gray piles of residue are mine tailings or stamping plant leftovers called “stamp sand.” Several bona fide ghost towns hide in the woods, too, especially between Calumet and Copper Harbor.

At Central (watch for the small brown sign on U.S. 41 about 11 miles north of Mohawk), an exceptionally rich mine produced nearly $10 million by 1898; the surrounding town grew to 1,200. Today, nature has all but reclaimed Central, with just a few clapboard houses creaking in the breeze. Turn right near the top of the hill for a look at the mine ruins and rows of house foundations. Watch where you’re walking.

Just south of Copper Harbor on U.S. 41, another sign announces your “arrival” in Mandan, directing you down a dirt road disappearing into birches. Follow it south for about 50 yards and homes suddenly erupt out of the woods, lined up in a tidy row. Welcome to Mandan, the last stop on a trolley line from Hancock.