A marvel of Byzantine engineering under the streets of Istanbul.

Experience a quartz crystal sound bath inside a storied, all-wood sound-chamber.

The world’s first statue of the late Apple co-founder.

The true meaning behind this sculpture remains unknown.

From cartoon characters to tiny tanks, a guerilla sculptor's little bronze statues are hidden throughout the city of Budapest.

The oldest private art gallery in all of Hungary.

Electrical curiosity museum housed in an old transformer station.

Legions of Roman soldiers bathed in this ancient spa complex under a Budapest transit station.

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

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

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

Late at night, the bust of the "Dracula" actor was snuck onto the facade of this Budapest castle.

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

A Hungarian pharmacy museum with a box full of mummy powder.

Tucked away near more famous landmarks lies a statue meant to symbolize the confluence and continuing development of human culture.

The romantic garden was the epicenter of the Hungarian art scene in the 1880s.

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

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

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

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

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

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

Located right outside of Vienna, visitors can take in expansive views of an ethereal forest.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.