Lavish royal estate punctuated with heated greenhouses.

A 14th-century Serbian Orthodox church that was once converted into a mosque under the much-disfavored Ottoman Empire.

A mural recalls a fictional woman who once lived at 23 Quai du Commerce, 1080 Brussels.

Belgium's national heroine turned spy sacrificed her life to combat German occupation.

A naturally beautiful, seemingly bottomless deep blue spring.

Portugal’s highest lighthouse has one of the most impressive focal planes in the world.

Drink among marionettes at this pub inside a historic puppet theater.

One of the oldest structures in Helsinki is this burrow grave that dates back to the Bronze Age.

An abstract representation of weather in Sweden.

Eat a Nobel banquet from any year in the basement of Stockholm's City Hall.

A miniature model of the iconic Stockholm department store.

Museum dedicated to the terror regimes of Hungary.

Also known as Uncle Karl, the beloved bronze copper keeps a watchful eye on St. Stephen’s Basilica while people rub his lucky belly.

Before it was buried by volcanic ash, this fast-food restaurant fed the hungry hordes of ancient Rome.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

A limestone grotto where daylight filters in from below and turns the water a beautiful turquoise. Also home to a small underwater nativity scene.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

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

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

A tiny church on a man-made island in the Adriatic.

Climb into Albania's communist history while enjoying a spectacular ocean view.

The “City of Stairs” sits high in the Andes, above the world’s largest underground copper mine.

This narrow street is packed with street vendors and bars selling chicha.

Two stunning 17th-century libraries and a cabinet of curiosities.