Learn about the last river many crossed to find freedom from slavery in the United States.

Walk a trail through a historic Quaker town that outlawed slavery in 1777 and was a major waypoint on the Underground Railroad.

This dig site outside D.C. is known for its exceptionally high density of baby dinosaur fossils and dinosaur eggs.

The trials and tribulations of marking Poe's grave.

Eighteen miniature death-scene dioramas.

A priceless collection of the Nation's cryptologic history.

The overgrown remains of one of the premier auto-racing speedways in the Midwest—and also one of the most deadly.

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."

While knives are the main feature in this store, visitors will also find dinosaur bones and meteorites.

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

A psychedelic tribute to one of Georgia's most unique artistic visionaries, out of place and time in the heart of Atlanta.

Wallabies live naturally on this Irish island.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

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

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

A natural sandstone bridge hidden in the Sewanee forest.

This 19th-century hotel and spa hosted famous guests like like the Vanderbilt family, William Waldorf Astor, Helen Keller, and Jay Gould.

The longest navigable underground river in the United States is home to countless blind and albino animals.

The jewel of western Mexico's archaeological legacy is this tiered circular pyramid now covered in grass.

This concrete amphitheater offers an unforgettable view of one of Mexico's most beautiful canyons.

One of Mexico’s historic pottery-producing towns is home to a museum showcasing the craft.

Shocking dioramas of human torture, meant to promote human rights awareness.

These eerie outliers of the lightning bug family glow a mysterious blue color.