Something's watching you.

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

No one knows who built this strange cave of worship or exactly why.

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.

This massive underground salt mine now holds a sci-fi theme park in its depths.

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

This solitary monastery may hold the remains of Vlad the Impaler (but probably not).

The only museum with its curator—and her pets—buried inside.

Thousand-year-old Viking runes adorn an ancient Greek lion at the entrance to the Venetian Arsenal.

The most metal church of all time was built in record time because of an international, pious pissing contest.

This building has two facades of clashing architectural designs.

An homage to the medieval rulers of Bulgaria.

Outstanding, eerie frescoes and decorations fill this 19th-century monastery.

An ancient necropolis of magnificent tombs.

A perfectly preserved hill village where the buildings are painted like white lace.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

An enormous and lavish Gothic church in Czechia.

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

These locks on North America’s oldest canal are named after a porcine rock formation.

This giant roadside goose has been hailing travelers into a small Ontario town for over 50 years.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

Christ's blood preserved in a Belgian town.

The Guardian of Tallinn.