This striking royal residence is the largest Renaissance-style castle in Scandinavia.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

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

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

Vortex-shaped aquarium hosts Europe's largest school of piranhas and other ocean creatures.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Copenhagen's celebrated theme park and gardens.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

A Red Cross memorial museum at the site of the Niš concentration camp that operated for four eventful years during World War II.

Structure built from the skulls of vanquished foes.

Sweden's "good old days" painstakingly re-created in a model village.

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

First point in the Struve Geodetic Arc, a 19th century undertaking to measure the Earth's size and shape.

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

Estonia's largest creative city is a vibrant bohemian hub located within a former industrial complex.

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

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

A black cat protests the City Guild in Riga's Old Town.

Flamboyant architecture from the turn of 20th century.

3,000 market stands in five former Zeppelin hangars.

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.

Ever-growing collection of devils in art.