An acoustic anomaly with a mysterious cause.

A 35-foot-tall fork stuck in the ground outside an office building in Missouri.

You can walk through the first Boeing Air Force One, which famously carried JFK's casket from Dallas back to D.C.

A real flying saucer, contracted by the U.S. Air Force.

A monument to the two U.S. officers killed by North Korean troops while trying to trim a poplar tree.

The site of many tense prisoner exchanges across the Military Demarcation Line between North and South Korea.

Cairns built to bring travelers good luck stretch across the land like miniature stone mountains.

South Korea's largely symbolic, barely used gateway to the North.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

A tiny, unassuming park in Tampa that belongs to the Republic of Cuba.

A gleaming white tower in ornate Indian style soars above the low-slung bungalows of north Tampa.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

19th century tunnels burrowed under Liverpool.

Climb inside an iron crystal magnified 165 billion times its normal size.

The name of this ancient Indonesian temple translates as "Elephant Cave" but it could be more accurately called "The Hellmouth."

Hindu temple of the dead home to hundreds of long-tailed macaques.

The world's longest known cave system.

One of the few surviving street funiculars in the world.

A blooming house of worship for the masses.

Giant relaxing Buddha in Malaysia.

The most playful of the life-sized statues that make up Singapore's "People of the River."

The "lovely red Vega" of the legendary record-settling pilot.

Breathtaking and huge 430 year old maps of Italy.