One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A British plaque explains that a house was built using the spoils of the first international golf bet.

The fountain marks the area where hundreds of accused witches were burned at the stake.

Rotterdammers' dirty minds gave this santa a dirty nickname and cursed it to a life of wandering.

The works of poetry's biggest names grace the walls of the city of Leiden, all carefully painted by hand.

The first museum in the world devoted to sexual gadgetry.

Macabre astrological automaton clock dating to the late 1400s.

Walk through Czech history in Prague's largest graveyard.

Famously misunderstood wonder of the ancient world

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

These medieval skyscrapers dominate the skyline of this small Tuscan town.

These gutted monastery ruins still stand proudly in the middle of the Italian countryside.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

A sinister pyramid in the Frari contains the heart of the famous neoclassical sculptor.

A rare example of an octagonal Catholic church.

Pilgrimage site for star-crossed lovers.

This Italian foot path winds through the mountains via 52 individual tunnels.