Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This massive subterranean fissure is known as the "underground Grand Canyon."

Gustave Eiffel's masterpiece until the Eiffel Tower was built.

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

A popular European tradition makes its way to the states on one of America's most famous bridges.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

A dilapidated dock tells the story of Titanic’s missed arrival.

Elevated freight railway turned wildly successful urban park.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

An experimental, automotive replica of Stonehenge.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

This vintage train once gave new meaning to “swimming upstream.”

One of the largest private collections of fossils in the world.

A cemetery housing wild west legends in South Dakota.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

In one of the smallest countries in the world stands an original Salvador Dalí sculpture.

Quite simply the largest tree in the world (by volume).

This coastal rock formation resembles a churning cauldron at high tide.

Fifty years after a “blast blasted blubber beyond all believable bounds,” this idyllic natural area commemorates the carnage.

The largest spring in Northwest Arkansas is also home to a sprawling botanical gardens and a historically significant bluff.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

One of these two land speed record-breaking vehicles went so fast it shattered the sound barrier.