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

A statue in Budapest's Liberty Square honors the former U.S. president's efforts to end the Cold War.

This quaint Hungarian railway system is operated exclusively by children between the ages of 10 and 14.

Sitting beneath an unremarkable residential building is a museum devoted to classic Pinball.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

This high point in the Great Smoky Mountains is said to be home to the chief of all bears.

Once decrepit and slated for demolition, now one of the longest pedestrian bridges in the world.

This funicular railway rumbles along for a mile up the nearly vertical face of Chattanooga’s Lookout Mountain.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Singapore's landscaping project is home to 18 incredible Supertrees.

Across this single-file rope bridge is what has been claimed to be the edge of continental Asia.

Glasgow's own "tipsy" temperance monument.

One of the first monuments dedicated to the accomplishments of the great Vice Admiral, Horatio Nelson.

Launch site for nuclear war against Western Europe.

Sculpture garden of religious statues made it through Soviet rule.

A narrow strip of land is home to the tallest migrating dunes in Europe.

Finland's northernmost zoo is home to the country's only polar bears.

Running under an entire mountain, the longest highway tunnel in North America is kept fresh using portal fans and jet fans.

This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

The king of U.S. high points towers over every other peak on the continent.

These engineering masterpieces are a dominant feature of the Belfast skyline.

The modern birthplace of Irish freedom.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.