This homegrown adoption center offers a wonderland of feline companionship.

Over a dozen Native American earth mounds dating back over 2,000 years dot this Tennessee archaeological park.

This park contains one of the largest concentrations of cedar glades, a unique and rare ecosystem.

This defunct, fortress-like prison has been the setting for several movies.

A reclusive Memphis neighborhood is home to decades worth of misunderstood Masonic folk art.

Elvis's own personal tropical hideaway.

This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.

Walk the whole Mississippi River!

Mile-long cave system near Great Smoky Mountains.

This head-spinningly bizarre Depression-era art cave is wall-to-wall quartz and Jesus.

The secret city built by the Manhattan Project.

More than five miles of underground passageways.

Visit this playground of waterfalls, caves and sinkholes.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

All that's left of the quintessential "cabin in the woods."

Home of an evil witch famous within southern folklore.

Enormous lake at the bottom of a unique cave system.

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

Three prestigious academic collections come together to create a world-class natural history museum.

The pleasant woodland cemetery that has inspired more than its fair share of wild legends.

Tour the world's largest deep-hole dimension granite quarry, where you can view the plant where gravestones are made and roll a ball down the outdoor granite bowling alley.

Even Henry David Thoreau found this glacial pothole irresistible.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.