An industrial site turned into Hungary's most cherished natural wonder.

This statue of a falling man commemorates a teenage martyr of the Hungarian Revolution.

Hungarian self-built castle.

One of the largest barracks of the Austro-Hungarian monarchy's military is now an abandoned ruin.

Electrical curiosity museum housed in an old transformer station.

This hidden art nouveau gem was designed by an architect in search of a national style.

A fake Transylvanian castle houses a cathedral of antlers.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

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

The abandoned "Red Star Train Graveyard" is the final rusting place for precious artifacts of train history.

Museum dedicated to the terror regimes of Hungary.

Once the home of a hermetic monk, this cave now houses a small church.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Was there a small "backpack nuke" hidden in the attic? JFK apparently thought so.

Obscure Freemasons still live in D.C.’s largest private residence.

These recently uncovered walls are all that's left of Washington, D.C's first defense contractor.

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

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

Government testing at the asylum briefly explored using marijuana as a "truth serum" on Nazi prisoners of war.

When it opened during the final years of the embargo, all the drinks and cigars were free.