Meet your friends, marry your true love, or tell your enemies to kiss your butt under this historic Pittsburgh timepiece.

An ancient Egyptian temple in the middle of Madrid, Spain.

The mysterious large white cross visible from the runway is a memorial to a massacre during Spanish Civil War.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

This unattributed sculpture in Amsterdam is hiding in plain sight.

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.

A clone-tree in Washington Square Park sprung from seeds that went to the Moon and back.

Where America's first doomsday cult awaited the end of the world.

This public park was the site of the largest civilian disaster of the Civil War.

A toxic ghost town sitting atop a massive coal fire.

The profile of one ill-fated deacon was emblazoned forever on this church window during the Halifax explosion.

The infamous Boston Mob ran rackets from an office here in the 1970s.

This popular Boston haunt is reminiscent of a time gone by, when slow cafes and sweet-smelling smoke wafting from patios was the norm.

The oldest Italian café in Boston, this spot also serves as a veritable museum of vintage coffee ephemera.

The first bell ever cast in Boston was cast by Paul Revere...and sounded terrible.

A mysterious stone embedded at the base of a historic Boston building.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

An enormous, inside-out glass globe built in 1935.

New York City's smallest piece of private property.

Within this beautiful Pittsburgh cemetery, a unique headstone bears witness to one man's eternal love for Jaws.

Once used to screen films for theater owners to rent, this historic building is now a start up hub.

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

The last street in Pittsburgh that's paved with wood.