The "stairway to heaven" lookout tower was built to resist weather, arson, and the laws of physics.

In an area where the remnants of WWI are discovered on a regular basis this preserved frontline trench may be the most amazing.

One of the deepest indoor swimming pools in the world.

Artwork tucked within the trees greets visitors with surreal sonic experiences.

A 14th-century fortified keep showcases the masterpieces of an ingenious 20th-century clockmaker.

A rare example of World War I trenches from the British front.

Hiding the longest subterranean river known in the world.

Climb inside an iron crystal magnified 165 billion times its normal size.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

Part modern art project, part traditional chapel, this see-through church is only substantial from the right angle.

Each spring, a dreamlike carpet of bluebells overtakes the forest floor.

The first museum dedicated to exploring humanity's cultural relationship with the celestial world.

The pyramid and dome deep inside the Dzūkija forest are believed to channel divine energy.

A small monument in Lithuania marks the geographic center of Europe—or at least one of the claimants.

Legend has it that Napoleon Bonaparte fell in love with this Gothic church.

The oldest funicular in Lithuania has been climbing this steep hill since 1931.

A narrow strip of land is home to the tallest migrating dunes in Europe.

Things aren't quite what they seem at this mind-bending museum.

The mile-long pier stretches from a ruined fortress out into the Baltic.

The widest waterfall in Europe is a natural wonder and one of the only places where fish are caught in the air.

Rent a barrel for a personal view of where the Baltic Sea meets the Gulf of Riga.

The widest natural waterfall in Estonia is a sight to see in all seasons.

This stunning limestone waterfall is the highest in Estonia.

This Estonian watchtower looks like a big tree with two giant bird nests on it, complete with a "golden egg."