A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Vibrant street art created with mixed media.

A lush indoor jungle fills this bustling Madrid transportation hub.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

These Bullet-scarred bunkers are haunting reminders of the Spanish Civil War.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

Lovingly nick-named the "Brick Dick" this municipal tower was winner of the World's Most Phallic Building Contest.

Look closely and you’ll notice that the color changes a third of the way up the tower.

A Borgesian work of art that may blur the line between fiction and reality a little too convincingly.

A treehouse assailed by the elements and the government, now gone.

This double-arched masonry highway bridge is the only structure of its kind in Minnesota.

After the musical legend's death, his memorial was mysteriously graffitied in gold.

This old residential building was once the largest flour mill in the world.

One of the world's premier laboratories for hydraulic engineering research takes full advantage of the water's power.

Downtown Minneapolis mixed art and function by turning some of their sewer covers into works of art.

This rare vessel mixed luxury with labor before being converted to a museum and sometimes haunted maze.

One of two giant blue cockerel statues erected with an intentional double meaning.

This kaleidoscopic mural shows Bob Dylan throughout his transition from young troubadour to Nobel laureate.

This iconic water tower and failed bandstand is open for panoramic views once a year.

This taxidermic smorgasbord was co-created by an artist poached from the Museum of Natural History.

The basement bowling alley of this St. Paul dive bar is decorated with thousands of dollar bills.