The building that inspired Shirley Jackson's "The Haunting of Hill House."

The perfectly named cave drop is the deepest in the continental United States, almost matching the height of Seattle’s Space Needle.

An acoustic anomaly with a mysterious cause.

A small horde of mythical creatures lurk almost imperceptibly within the museum's wildlife dioramas.

An Iowa town celebrates its heritage with the tallest working Dutch windmill in North America.

At this Minnesota state park you can easily wade across the source of the mighty Mississippi.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

The Twisted Trees of Alticane are an unnerving grove of Quaking Aspen, apparently mutated from a single source, giving them a twisted and unnatural appearance.

This historic motel standing at the "crossroads of America" offers a radio in every room and was saved by local protesters.

A view-altering observatory at the University of Texas.

A metal ring in the middle of the road marks the exact spot where the Soviet satellite crash-landed in 1962.

The "mysteries" of this quintessential roadside oddity were almost destroyed by neglect but were saved by fans of kitschy wonder.

A humble homemade ride attracts visitors from around the globe to this small Midwestern town.