A huge wooden clock that is so beautiful its creator was forcibly blinded.

This 13th century Gothic brick castle is the largest in the world by surface area.

This biographical museum honors the groundbreaking scientist at her birthplace in Warsaw.

The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

The last king of Poland was interred in this church nearly 200 years after his death.

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

An underground city of salt.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

An old hill fort covered in over 100,000 crosses is a symbol of Lithuanian nationalism and beliefs.

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

This micro-nation may be some sort of prank, but its constitution sure seems official.

This magnificent Art Deco church is a reflection of Lithuania’s turbulent history.

The world's first invisible city square is an homage to a man who pushed the boundaries of art.

The oldest housing complex in Riga is a mini timeline of architectural trends.

This charming Latvian lane doubled as Baker Street on the Soviet Union’s version of Sherlock Holmes.

The reconstruction of this prominent building fulfilled a long-written command.

Flamboyant architecture from the turn of 20th century.

The Guardian of Tallinn.

"There's nothing there," and other lies the KGB told us.

Replica of mosque destroyed by Russia in the 16th century.

Russia's own leaning tower was built on a tragic historical fable.

A former military outpost of Ivan the Terrible, the 16th-century church contains some of the rarest examples of Eastern Orthodox mural paintings.

Russia's giant concrete QWERTY keyboard is likely the largest in the world.