Home to items never before seen by the public.

A reproduction of earth's many biomes.

When ecosystems collide in the arid Southwest.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Eighteen miniature death-scene dioramas.

Berkeley Hot Springs presents to you "the only outdoor monument to presidential bathing."

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

Op-art architecture designed for happiness.

The prototype for all Nazi concentration camps.

Among the ostentatious rococo ornamentation of this church, an image of death cuts the life-thread.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Go surfing on this urban wave, "hacked" by local surfers.

King Ludwig I's collection of beautiful women.

Final resting place for the Triangle Shirtwaist fire’s unidentified victims.

Small monoliths of several varieties of stone sit alongside a wooded path in the Bronx.

An artist's cute bronze subway sculptures belie his violent artistic past.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A discreet little stairway on St. Nicholas Avenue leads to a quaint and unexpected cobblestone street of 19th century wooden rowhouses.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

At 207 feet, one of the world's longest continuous escalators.