Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

This former maximum-security prison is creepy, sobering, and supposedly haunted.

The highest point in Tennessee, Clingmans Dome bears witness to the ravages of one type of insect.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

A 1960s damming project turned one family’s hilltop cemetery into an island.

Mysterious ancient boulder carved with petroglyphs in the mountains of Western North Carolina.

Step back in time on this preserved 1800s farm.

Cherokee alphabet, proof of ancient North American Jews, or just a hoax?

An abandoned town is hidden in Great Smoky Mountains National Park.

The art studio of an early 20th-century painter, hidden amid the Great Smoky Mountains.

An unfinished rail tunnel that has since been used to house cheese and bats.

One man’s religious convictions led him to build this stone castle meant to withstand an apocalypse.

The highest point in Alabama was almost completely deforested, but is now home to protected towers and trees.

Visit this playground of waterfalls, caves and sinkholes.

Mile-long cave system near Great Smoky Mountains.

This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

This building contains handprints that are well over a century old.

A white oak with property rights.

A curious whirlpool formation supposedly capable of entangling or engulfing branches, tree trunks, or whole rafts full of hapless tourists.

The picturesque southern city served as the zombie-filled town of Woodbury in 'The Walking Dead.'

The scant remains of this flooded historic village can be explored in one of the most remote areas of the Great Smokies.

Giant instrument-shaped home in Fayetteville, Georgia.

Like Mars, but much closer.