In the 1940s, Italian architect Mario Cavallè built a dozen of these round homes in northern Milan.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

This grisly effigy displays an early Christian martyr who was skinned alive and beheaded.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

This camera store in Milan holds one of Europe’s largest collections of luxury-antique cameras.

Artistic tombs, monuments, and a beautiful "Hall of Fame" lurk inside this cemetery.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

Taxidermied animals galore, by appointment only.

A display of everyday life in the area that was unveiled during the 2012 Summer Olympics.

Hidden beneath the streets of London is a secret subway that only carried mail.

The spot where Oxford garnered its name was also home to a medieval philosopher and includes a house covered in statues.

Site of the first hot air balloon flight conducted by the first English balloonist.

This nondescript building was the birthplace of Morris cars.

The shop where the girl who inspired the beloved character once bought sweets is now a book-themed commercial curiosity.

This centuries-old pub boasts a collection of more than 4,500 snippets of neckties from around the world.

The beams of the New College, Oxford dining hall come with an amazing story.

A plaque marks the humble origins of an artistic muse who embodied the ideals of Pre-Raphaelite beauty.

Once one of the largest rooms full of books in the world, this bookstore basement is still a treat for bibliophiles.

An extraordinary collection of scientific instruments - and Einstein's chalkboard - inside the world's oldest purpose built museum building.

Hidden in plain sight, this creepy sculpture watches from above.

The spot where three Protestant clergymen were burned at the stake during the reign of "Bloody Mary."

This 11th century tower is said to be the oldest building in Oxford.

A hidden plaque is the only reminder of the lost palace where two storied English kings were born.

A plaque is all that remains of a lost Oxford transport hub.