Colorful Native American paintings are hidden within this small cavern.

Protected from the elements, these Native American rock paintings have survived approximately 250 years.

Massive still life just off the highway in Kansas.

The idyllic colonial home of the artist behind the famous portraits of George Washington and Thomas Jefferson.

A controversial magical figure is hidden within a diorama of the city.

A masterpiece of LGBT art has been restored in what may now be the most valuable restroom in America.

This enormous 32-foot painting depicts Poland's greatest medieval battle in glorious detail.

A program of Communist glamour in post-Stalin Poland is preserved in this colorful museum.

This small museum is basically a time capsule of daily life in the Soviet Union.

Hidden in a metro shop under a shopping mall, this small museum tells the story of one of the world's largest urban transit systems.

Moscow's most popular cemetery includes the graves of numerous cosmonauts.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

Back in the tiny USSR.

The tallest hotel in Europe.

This building holds the embalmed remains of the leader of the Bolshevik Revolution.

World's largest bell sits on the grounds of the Kremlin in Moscow.

One woman’s obsession gave birth to this lovely oddity at the Boston Public Library.

Reverend Jen's unique museum/living room showcases her troll collection.

A veritable variety of odds and ends.

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

Historical figures from New York City's Catholic community reside in Midtown.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

Deep under Manhattan is the largest construction project in city history. So far, the project has taken the lives of 23 workers, or "a man a mile."

Recovered suit of a cannibalistic West African gang.