A tunnel with windows, so you don't miss out on the impressive views.

Take a steam-powered ride straight out of the past on this Appalachian rail line.

The site of the one and only battle of Lord Dunmore's War.

The largest burial mound in the United States holds the remains of prehistoric West Virginians.

Beyond the usual stories that attend old prisons, this one has deep bloody undercurrents.

Come face to face with the ferocious visage of the serpent-headed mother goddess of the Aztecs.

A barbarous band of serpents guard the bases of these Aztec temples.

This strange sculpture of a menacing skull surrounded by sun rays was discovered at the foot of the Pyramid of the Sun.

Many people don't realize there’s a lot going on in—and below—the world’s tallest triumphal arch.

This one-window stand has been home to a giant vat of slowly simmering meats and an array of unique tacos for almost 50 years.

Superstitious? Discover the witchy side of Mexico through its largest esoteric market.

Mexico City's largest market contains a Willy Wonka-esque wonderland.

These haunting ruins of a 700-year-old Prehispanic city have witnessed centuries of wars and massacres.

Explore the atmospheric ruins of an abandoned convent in the dense forests of Mexico's first national park.

A church dedicated to the Mexican skeleton saint.

This pyramid is dedicated to all those who suffered martyrdom for civil and religious liberty in Scotland.

The oldest continuously operating fish market in the United States.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

This large, castle-like structure is hidden amid the mountains on the grounds of the Utah State Hospital.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

Where monkeys run wild and the humans are caged.

Two insane asylum bodies embalmed by an amateur.