This gem from the industrial age helps visitors and residents alike traverse hilly Stockholm.

The Swedish flag over this small naval fort signals that the nation is at peace.

The scars of a remarkably organized public protest to save 13 elm trees are still visible in this Stockholm park.

Sweden's oldest animated sign is still lighting up the skyline today.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

A man has revenged his true love's betrayal through tears and stone genitalia.

An ancient Viking runestone hidden in plain view in Stockholm's old town.

A hidden bathhouse in one of Stockholm's oldest and busiest neighborhoods is open to anyone who can find it.

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

A cathedral resurrected from the ashes of one of Europe's greatest urban fires.

Pigduck of Turku.

These mysterious Viking chess pieces spent centuries hidden on a remote Scottish island.

A collection of collections ranging from dentistry to minerals.

William Blake claimed to have painted this gothic masterpiece after encountering this nightmarish being in a vision.

Villas that once served as playgrounds for the rich now fall away in decay.

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

An impressive armored bronze effigy marks the tomb of one of the medieval era's greatest warriors.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

This statue of a falling man commemorates a teenage martyr of the Hungarian Revolution.

Those who own or stay at this 500-year-old, allegedly cursed house often meet terrible fates.

'The Letters of Utrecht' lays out a ribbon of poetry one letter at a time, with no final verse in sight.

In the days before house numbers, these colorful signs held clues about various buildings' purposes.

This macabre painting of a Shakespearean scene looks like something out of a nightmare.

This marine reptile was discovered by one of the 19th century's greatest fossil hunters.