Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A partial tunnel blasted into a steep ridge is all that remains of a failed railway across Arizona.

This 40-room dwelling tucked within a cliff was built by the basin's prehistoric residents.

This 80-year old mannequin is so lifelike it is believed to be an embalmed corpse.

If you can look past the nearby sewer pipes, this urban sinkhole grotto is a mini-paradise.

Mexico's astounding mummy museum with "the world's smallest mummy."

A 500-year-old series of tunnels long believed to be folkloric was uncovered beneath the streets of Puebla.

A scientific repository of goiters, boils and other ailments throughout Mexican history.

A uniquely robust and historic look at Mexico's omnipresent dance with Death.

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

An elaborate Mayan city shrouded in alien conspiracy revealed the tomb of Pacal the Great.

An ancient system of freshwater caves filled with animal bones, including that of species long-extinct.

A disquieting Aztec sculpture displays hundreds of stone skulls representing the victims of human sacrifice.

High atop a Mexican rainforest mountain, this ancient pyramid once drew pilgrims countries away.

An Aztec temple, the largest man-made pyramid in the world, sits buried in earth with a Spanish church set on top.

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.

The famous artist couple lived and worked here, in two different houses separated by a bridge.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

A jaw-dropping "megalibrary" that turns book-browsing into a geometric adventure.

These azure waters were thought to lead to the Mayan Underworld.

Part bookstore, part café, and part forest.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

Urban explorers embraced America's now demolished first suburban mall, south of Chicago.