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Approaching exit 374 on the I-90, just west of Sioux Falls in South Dakota, you may be tempted to stop at a roadside jack-in-the-box. Not Jack in the Box, home of the Spicy Sriracha Burger, but a sculpted metal jack-in-the-box that wields a knife and smiles while crying blood.

The maniacal figure is one of over 50 unsettling metal creations created by local artist and former sheep farmer Wayne Porter. His Porter Sculpture Park, open since 2000, is home to all manner of nightmare fuel, including a screaming head with a hand bursting from its scalp, a spiky, sharp-toothed dragon with empty eye sockets, and a head perched atop a leg, its eyes and mouth sewn shut.

Handwritten placards alongside the sculptures provide a bit of context—or further confusion, depending on your perspective. (The signpost beside the head-on-a-leg explains that “In order to be wise, one first must be mangled.”)

Visit Atlas Obscura for more on Porter Sculpture Park.

More eye-catching outsider art:

• A former electrical substation is now home to an eccentric junk art masterpiece
• Giant pink robots and post-apocalyptic Christmas scenes dominate this park 
• Grandpa Rainbow felt his neighborhood needed color, so he picked up a paintbrush and went to work