This giant expressionist head crowns a museum devoted to a beloved Mexican leader.

Part bookstore, part café, and part forest.

The only castle in North America to ever house European sovereigns.

66,000 pieces of art, donated by one of the world's richest men.

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

An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

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

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

Adolph Sutro's little-known, geographically inaccurate, deprecated monument.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

At Chicago's revered Field Museum, visitors are invited to learn about and literally explore DNA.

What was once one of the country's largest confectionary plants is now an abandoned ruin, but is still pretty sweet.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

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

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

The final resting place for the remains of 143 Habsburg royalty.

The celebrated eyesore created by starry-eyed sweethearts.

Home to items never before seen by the public.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.