An empty relic of the Moscow Olympics crumbles away in Estonia's capital.

This lake-bound geographical marker sits at the point where three European countries intersect.

The past, present, and future of Russia's signature alcohol is remembered in the world's only museum dedicated to the starchy spirit.

This Russian museum stresses the importance of keeping clean and even holds one of Pavlov's dogs.

A man-made island fort that has housed soldiers, scientists, and ravers.

The oldest museum in Russia is home to a fascinating collection of nearly two million anthropological artifacts and anatomical curiosities.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

An abstract monument to a symphonic composer.

A subterranean house of worship carved right out of the bedrock.

Architecturally stunning library serves as the hub of Finnish scholarly life and culture.

Stunning examples of Russia's 18th-century wooden architecture.

The world's first ice hotel is still one of the most elaborate and beautiful.

A series of modernist treehouse hotel rooms grace the outskirts of an Arctic forest.

Monastery, army base, and infamous Soviet Gulag in the far Russian north.

This fantastical icy castle is built anew every winter.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

This fairytale inspired, warped building houses restaurants, shops, and a radio station.

This chimerical bridge/tunnel appears to dead end right into the sea.

This Swedish astronomical clock was in storage for almost a century before its glorious workings were put on display once more.

This hobbit-y little hot spring may be the oldest spring used by humans in all of Iceland.

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

An enormous, inside-out glass globe built in 1935.

An 18th century wonder of the world, lost in WWII, re-created at the Catherine Palace.