Tomorrow is Halloween, and in keeping with the vibe, we’ll travel to Wisconsin to check out three spooky geo-sites. Witches, fairies, devils, gnomes, and floating orbs? Who knew the Badger State could be so scary? 😈🎃🧙♀Happy Halloween everyone!
Sharon Lyon
Editor, GeoLifestyle
Witches Gulch at the Wisconsin Dells
Jason Ross/Shutterstock.com
Located 50 miles north of Madison, the Wisconsin Dells is a series of picturesque sandstone cliffs towering over the Wisconsin River. The Dells have been a scenic vacation destination since the 1850s.
The area is separated into the “Upper Dells” and the “Lower Dells” by the Kilbourn Dam.
Witches Gulch is a narrow slot canyon within the Dells. The name originates from a Native American legend in which serpents and evil spirits are said to have formed the canyon.
In 1875, the debris-choked passage of Witches Gulch was cleared, and boat tour landings began.
Geology: Over 500 million years ago, the shallow Cambrian Sea covered the area. Sand and silt were deposited, later lithified to become the Cambrian Mount Simon Formation, a well-sorted quartz arenite, overlain by the Cambrian Wonewock Formation, a carbonate-cemented sandstone.
Approximately 1 million years ago, several glacial lobes extended into parts of northern and eastern Wisconsin. The area of the Dells is on the extreme eastern margin of a “drift less” area, untouched by the glacial ice.
Around 15,000 years ago, a continental glacier melted creating Glacial Lake Wisconsin, a massive lake held in place by an ice dam. The ice dam burst, and an enormous amount of water, rock, and debris carved deep gorges into the sandstones.
Today, the Wisconsin River continues to sculpt the sandstone cliffs.
Experience the Wisconsin Dells by taking a boat tour. Operating season is April–October.
Witches Gulch is on private property and is not accessible by hiking from the land: It is only reachable by boat tour through the Upper Dells.
From the boat landing at Witches Gulch, hike the wooden boardwalk to experience the spooky moss- and fern-covered gorge, described as a “fairy-like” setting. 🧚♂🧚
The boat will also take you to Stand Rock, a towering sandstone pillar famous for the “dog leap,” where a dog jumps across the gap from one tall rock to another.
Devils Island, Apostle Islands National Lakeshore, Wisconsin
Michael Tatman/Shutterstock.com
Devils Island is one of the 22 islands in the Apostle Islands National Lakeshore in western Lake Superior.
It was once thought there were 12 islands in the Apostle archipelago, hence the name Apostle.
Evil spirits or crashing waves? Devils Island’s name may be derived from a 1899 account of a Native story in which an evil spirit lived there… Modern Native scholars question this account.
During times of heavy surf, waves crash deafeningly against Devils Island’s sea caves and around its arches, adding to its eerie atmosphere.
Area geology: Devils Island is composed of Mesoproterozoic (1 billion-year-old) Devils Island Sandstone, which is part of the Bayfield Group and the Keweenawan Supergroup.
The Devils Island Sandstone is characterized by thin bedding and well-rounded quartz grains, by ripple marks, and by its pink to white color.
The sandstone is interpreted as being a fluvial deposit in the center of the Lake Superior synclinorium. Streams deposited the sand in the enclosed basin, probably under desert conditions.
No fossils are present in the formation.
The Devils Island Sandstone is more porous and friable than the other sandstones of the Bayfield Group, enabling the erosion of more striking and larger sea caves.
Trip tips: Take a boat tour or water taxi to Devils Island. Trails lead from the three boat landings to the lighthouse.
The island is also popular with kayakers.
View the striking sea cliffs and caves, best seen near Squaw Bay, to the southwest.
The island is wooded, and the dark foliage gives it a forbidding appearance. 🌲🌳🫣
In the summer, Park Service volunteers staff the island. Then, visitors can climb the Devils Tower Light, built in 1894. It is the only Apostle lighthouse with its original Fresnel lens.
Fun fact: The northern tip of Devils Island is the northernmost point of Wisconsin.
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The Devil’s Punchbowl is a scenic bowl-shaped landform along the Red Cedar River Valley. Surrounded by layered rock faces dripping with groundwater, the area is covered with ferns, mosses, and sedges. A small waterfall spills over the top edge.
Spooky tales: To this day, stories of haunting ghosts and floating orbs surround the site. 👻Gnomes climbing up the rock walls have been spotted.
No one knows how the landform got its name, but the Devil’s Punchbowl was once owned by the University of Wisconsin-Stout. Their mascot is the Blue Devil.
Area geology: The surrounding rock consists of the Cambrian-aged Eau Claire Formation and the overlying Cambrian Wonewoc Formation.
The porosity of the Wonewoc sandstone allows water to percolate through the rock. When the groundwater meets the more impermeable, shaly Eau Claire Formation, the water flows sideways and over the cliff face.
The formations are part of the Sauk Sequence, major lithostratigraphic units that overlie Precambrian rocks of the North American craton. The sequence consists of nearly flat-lying marine sandstones. They are bounded on the bottom by the widespread Precambrian-Cambrian unconformity.
As Pleistocene glaciers melted, massive amounts of meltwater and outwash eroded and carved the sandstone, hollowing out the circular ravine.
Trip tips: The Devil’s Punchbowl is owned by the West Wisconsin Land Trust and is free to visit.
There are two short trails. The one to the top of the falls is an easy walk. The second trail is a challenging stairway down the slope and into the bowl. You must stay on the trails.
Stand at the base of the natural amphitheater to experience the cool, flowing water surrounding you.
In the winter, the water freezes, forming a spectacular scene of cascading icicles. The small creek in the middle also freezes, allowing you to get close to the frozen waterfall.
The Punchbowl has a unique microclimate and supports more than 200 vascular plant species. It is also home to 19 species of land snails.
From sites with haunting names, to formations with Halloween-esque shapes, these spooky geological features provide the perfect seasonal trip ideas for geo-enthusiasts.
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