A 30-acre garden inspired by the principles of modern physics.

These fantastically named natural pools look like something out of a Scottish myth.

This abandoned five-star hotel is now a five-star urban exploration destination.

The best place in the world to buy tinned fish.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

The world's oldest bookshop still in operation.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This volcanically volatile island town is home to an abandoned series of tunnels left by the Japanese during WWII.

Breathtaking and huge 430 year old maps of Italy.

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

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

Romania's triumphal arch looks out over Bucharest.

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

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

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

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

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

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

This Bronze Age tomb is the centerpiece of a clearing within a beautiful Irish forest.

These imposing walls and towers look more like the ruins of a fortress than a monastery.

Dublin's "Dead Zoo" serves as a window to Victorian museum design.

Where commuters walk through remnants of an ancient Greek necropolis.

An ancient octagonal weather station named for the eight Greek gods of wind.