Yooperlite Scouting: Search for Glowing Rocks on Michigan’s Shores

Travelers are increasingly curious about the nighttime world—so much so that Booking.com named nocturnal tourism one of the top travel trends of 2025. As an astrotourism writer and author of National Geographic’s "100 Nights of a Lifetime: The World’s Ultimate Adventures After Dark," I’ve traveled the globe to find the world’s best after-dark wonders. This book, which hit shelves in December 2024, covers 100 top night experiences, including one outing that’s near and dear to my heart (and my home in Cleveland, Ohio): searching for “glowing” rocks on the shores of Lake Superior.

Learn more about how to enjoy this experience yourself, especially in one of the best places in the world to see the rocks—Michigan’s Upper Peninsula:

Michigan’s far-flung Upper Peninsula (UP), the northernmost stretch of the state, brims with natural beauty, from craggy sandstone cliffs and Milky Way—splashed skies to the glow-in-the-dark stones that send rock hounds on twilight treasure hunts all summer long.

These vibrant rocks, nicknamed Yooperlites, are coarse gray syenite rocks that contain the mineral sodalite, which fluoresces under UV light. (Officially, the rocks are known as fluorescent sodalite-bearing syenite.) By day, the igneous rubble looks like your average stone. Come nightfall, beneath a UV glow, sodalite absorbs the light, then emits it in another wavelength. The result: a stone flecked with tangerine streaks that looks like something from "Alice in Wonderland"—not a stone on the shores of northern Michigan.

Scientists believe Yooperlites stem from magma some 1.1 billion years ago. Glaciers from the last ice age scooped the syenite rocks out from underground in present-day Canada, then scattered them across the Laurentian Plateau (the Canadian continental shield) and across the Great Lakes, particularly in Michigan.

The stone gets its nickname from a term for UP residents, known as Yoopers. Though Yooperlites are most common in Michigan, particularly along the rocky shores of the far north Keweenaw Peninsula and Grand Marais, you can spot them across the whole of the Great Lakes region’s pebble-dashed shores.

You’ll need specific gear to find these glowing rocks, including a filtered 365-nanometer UV light, a headlamp or flashlight for safety, and sturdy shoes that can get wet. To improve your odds, join an expert-led rock tour, which will also provide the necessary equipment. Michigander Erik Rintamaki, the first to find and report on the state’s Yooperlites in 2017, now leads after-dark excursions to help visitors spot these stunners in the UP.

You can see the rocks any time of year, but timing your glow-in-the-dark adventure for late spring, summer, or early fall is best; Michigan winters get cold, dark, and icy. Spring, when ice and snow have shifted the rocks, is particularly promising.

Though keeping your eyes on the ground is tempting, make a point to look up. Northern Michigan has some of the darkest, most star-drenched skies in the state—perfect for gazing at meteor showers, the Milky Way, and, on the luckiest nights, swirling auroras.

Where to Stay: Don’t look for Yooperlites just anywhere; sleep within steps of them at Fresh Coast Cabins, a family-owned escape on Michigan’s far north Keweenaw Peninsula. At this collection of hip and upcycled cabins on Lake Superior’s rock-strewn shore, you can search for Yooperlites—and the northern lights—right from your waterfront porch or the lake-view Finnish sauna.

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