Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Try not to get slimed in Tribeca.

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

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Budapest's Communist-era statues, banished to the suburbs.

Macabre astrological automaton clock dating to the late 1400s.

These slanted cubic abodes are a creative if odd solution to a zoning pickle.

A passage grave used in neolithic rituals.

A museum celebrating the Canadian forces that liberated Belgium from the Nazis replete with battlefield miniatures and multiple Gardens.

A little sculpture with a large wardrobe.

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

Yo, Adrian!

A restaurant and observation deck built in a unique broadcasting antenna.

A fascinating insight into daily life in the Eastern Bloc.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

Eighty million natural history specimens call this gargantuan museum home.

Pop culture has helped to keep this iconic British building from being destroyed.

A hands-off space for graffiti artists to hone and display their skills.

Scattered throughout London are ancient remnants of the city's former bounding wall.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.