An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

The former home of a mad diplomat is said to still be marked in bloody, arcane scrawls.

This cheese shop also houses a museum devoted to Dutch dairy.

Tucked in the back of a flower shop, its collection details the fascinating history of the Netherlands's iconic symbol.

This ominous Albanian fortress houses tanks and downed planes as a reminder of their victories over Western imperialism.

This beautifully preserved Ottoman house is steeped in history.

A naturally beautiful, seemingly bottomless deep blue spring.

This hydrochronometer was invented by a Dominican monk and is a prime feature in this garden.

An 18th century fountain and two columns are all that remains of Rome's forgotten river harbor.

This large, circular tomb is the final resting place of the first emperor of Rome.

An unremarkable wooden wheel built into the side of one of Rome's oldest hospitals was part of a policy to reduce infant exposure.

One of the most important yet well-hidden museums dedicated to the history of medicine.

Stone memorial that's said to predict the death of the pope and the site of the Cadaver Synod.

This museum is rotten with a century of wax medical deformities.

An extraordinary house museum and cabinet of curiosities in the heart of Florence.

Legend says this mysterious stone head belongs to a woman who was petrified by an alchemist.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

The graveyard is filled with beautiful funerary art and boasts breathtaking views of Florence.

After being destroyed by two separate fires, this monastery is now home to a small zoo and relics from dozens of saints.

An 80-year-old plane tree is devouring an iron bench at Ireland's oldest law school.

More than 5,000 artifacts donated by the people of the city, plus a room entirely devoted to the band U2.

Huge standing stones mark a site of megalithic mystery.

Throughout this shopping mall are medieval ruins that were discovered during the mall's construction.

The best preserved Paleochristian basilica in Rome hides a number of oddities and secrets.