Electrical curiosity museum housed in an old transformer station.

Bizarrely shaped rock formations in northwest Bulgaria come with equally bizarre legends.

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

A bridge destroyed three times: once as a ruse, then in an actual attack, and finally for the movies.

The remains of the last Bosnian fortress to fall to the Ottomans are still standing.

The world's oldest known salt mine.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

This former estate of a fascist leader is now a burnt out ruin leading to a system of secret tunnels.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

A whimsical bridge adorned with decorative dragons.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

This spire on an Austrian mountain is wrapped around a long spiral slide and has the world's tallest wooden observation deck.

Bizarrely-painted church designed by a controversial artist.

This Italian church is as beautiful as it is common, except for the real skulls decorating the many mannequins inside.

This military mausoleum captures the solemn grandeur that most memorials only aspire to.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

This one-time health resort was used by aristocrats around the world.

This domed temple was built in a hidden cave mouth as a refuge for sinners seeking absolution.

This abandoned Slovenian military barracks has become a punky-political art squat.

This ultra-modern burial building would have stacked the dead like a giant filing cabinet.

Sitting on an Italian hilltop is this surreal fortress built by the mad inventor of electrohomeopathy.

Italy's curious field of mud volcanoes is named for being both gross AND salty.

These "anatomical machines" are only one of the many strange items in this Italian crypt.

This medieval Italian town is a sheer (and beautiful) cliffside defense.