The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

Macabre astrological automaton clock dating to the late 1400s.

Apartment complexes built into huge repurposed natural gas tanks.

Trick water gardens from 1619 featuring a 200 piece mechanical theater powered by water.

The "dragon babies" of southeastern Europe.

A miniature train-ride through Slovenia's largest cave system.

This one-time health resort was used by aristocrats around the world.

A pair of connected skyscrapers form this symbolic gateway.

A public work of art that also provides some relief from the summer heat.

A whimsical bridge adorned with decorative dragons.

This memorial to the victims of the Romanian Revolution of 1989 is often compared to a potato on a skewer.

This Transylvanian church has changed its denomination four times.

Romania's triumphal arch looks out over Bucharest.

Nine centuries-old fortresses guard the walls of this medieval Romanian city.

Gigantic Romanian salt mines used to heal respiratory conditions.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

Something's watching you.

This snug medieval lane is one of the narrowest streets in the world.

Conspiracy theories and occult legends surround this mysterious natural rock formation.

A giant portrait of an ancient king looms over the river.

This once-derelict building is now one of the most beautiful bookstores in the world.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.