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Posen, Michigan: Mystery Valley

Mysterious cracks descend 150 feet into the ground. Signs warn, "Please Do Not Enter Earth Cracks." A failed nature attraction is now a free natural wonder.

14894 Leer Rd, Posen, MI
From MI-65 in Posen turn west onto State St./MI-634 and drive two miles. Turn left onto Leer Rd. Drive south 3.5 miles. You'll see the Mystery Valley sign on the left.
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Visitor Tips and News About Mystery Valley

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Mystery Valley

Mystery Valley is a nice scenic hike; earth cracks are beautiful and mossy. The lake was completely dry when we visited in mid-May. Watch out for ticks!

[Leslie Abraham, 05/20/2021]

Earth crack.

Mystery Valley

Art Poch, a real estate developer and outdoorsman, bought one of the largest sink valleys in Michigan in the 1950s, hoping to strike it rich with a tourist attraction that would rival Mammoth Cave and Carlsbad Caverns. He coined the name Mystery Valley for what's thought to be one of the largest known collapse structures in the Great Lakes region.

Art had grand visions of blasting open the swallow hole in a lake on the site that channels water underground to Lake Huron -- sometimes the water drains so fast that it creates a whirlpool -- so that tourists could explore the supposed underground caverns. He also envisioned playing carillon records in the huge sinkhole -- one mile long and 500 yards wide -- to fill the valley with music; and to charge fossil hounds to go rock collecting at a nearby hill.

Alas, either Art's money or health gave out. All that is left of Mystery Valley is a fireplace that Art had built for tourists, and a mildly awesome free public site where visitors can see large splits in the valley that gradually descend 150 feet from the surface. Signs warn, "Please Do Not Enter Earth Cracks."

[Matthew Gryczan, 10/17/2019]

Nearby Offbeat Places

World's Largest Limestone QuarryWorld's Largest Limestone Quarry, Rogers City, MI - 14 mi.
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Big Bald Eagle HeadBig Bald Eagle Head, Alpena, MI - 17 mi.
In the region:
45-Foot-Tall Bottle of Beer, Gaylord, MI - 48 mi.

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