Holy Grotto of Montserrat Monastery holds one of Europe's mysterious black Madonnas.

In the 1930s, a mysterious murder shook this Northamptonshire village–the identity of the victim remains a mystery to this day.

The first place where the scientific innovation known as radar was first demonstrated in Britain.

This unusual geoglyph was built as a warning so low-flying aircraft wouldn't scare the zoo animals.

Model aircraft soar over 360-degree views of the countryside at the start of England's oldest road.

A movable feast that is an East London institution.

In the 1970s, the citizens of several small villages came together to stop their homes from being destroyed for a new airport.

A historic house devoted to the teachings of a 1700's prophetess and her mysterious box of revelations.

This ancient Bedfordshire church was abandoned when the village's population slowly began migrating to new towns.

A herd of half-sized cow sculptures has stood in this part for nearly 50 years.

Museum celebrating the history of computers, especially their role in codebreaking.

This suburban British town holds secrets that would have made the druids proud.

A 19th century grave house with a unique message formed by the stone supports to the railing around the walls.

The first peace pagoda to be constructed in the Western world sits next to a small English lake.

Designed as a reminder of one of the darkest moments in Austrian history.

In the middle of a Vienna square, Roman ruins dating back some 2,000 years are on display.

A gift from Emperor Franz Joseph I to his wife.

Along the edge of this fountain are 365 smaller fountains that represent the days of the year.

An ornate private entrance to the Vienna subway built specifically for the emperor.

A patriotic medieval knight in driven-nail armor raised money for widows and orphans of WWI.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

Collection dedicated to funeral rites, equipment, and mourning rituals of the Viennese.

A rooftop restaurant hides in plain sight atop Vienna's Palace of Justice.