A historic observatory precariously perched at the "Top of Europe."

The world's tallest church tower reveals a spectacular view to anyone up to the task of climbing the daunting staircase.

A striking 12th-century-style castle built on the edge of a cliff.

Enter the cabin of a life-sized Hindenburg replica.

Bell tower juts out from a village buried under a lake.

One of the highest mountain passes in Europe has been ranked among the best driving roads in the world.

This work of engineering is imbued with elegance and ingeniousness.

Relics from an era long gone, sit idle outside this Estonian museum.

This striking memorial is one of Estonia’s most controversial Soviet leftovers.

A spectacular Petrine Baroque summer palace commissioned for Catherine I by Peter the Great.

During the Soviet era, the spire of this longstanding church was used as a radio transmission tower.

This medieval Estonian tower provides access to a series of tunnels that have been home to soldiers, punks, and fine art.

A secluded art gallery hidden within the cellars beneath Tallinn’s medieval monastery.

Walk along the medieval fortifications that have been protecting Tallinn since the 14th century.

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

A rare octagonal brick beacon on an isolated island in the Baltic.

In the waters outside Helsinki, a tiny island once used as a military outpost now welcomes visitors.

An abstract monument to a symphonic composer.

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

An alien church provides much needed silence in the midst of a Finland shopping center.

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

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

For a brief time in 1960s France, families could climb into a tiny submarine and be pulled along an underwater journey.

A French library that makes sure its love of books is writ large... giant in fact.