The ruins of this prominent glass factory yield hidden treasures buried among the jungle floor.

An abandoned jewel of a ballroom on the top floor of Australia’s busiest rail station echoes with the sounds of a bygone era.

The small peaceful island off the Venice tourist circuit is where the city began more than 1,500 years ago.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

The plague quarantine island home to the alleged "Vampire of Venice."

The oldest of Venice's plague quarantine stations, designed to keep the medieval city safe from disease.

This abandoned island off the Venetian coast has been a radical monastery, a political prison, and a secret Nazi base.

Venice's island of the dead.

Venice's "Island of the Mad."

From carts to cars, this leftover Roman bridge in France has managed to survive for centuries.

A walk through the historic city center, under the streets of Seattle.

A 90-year-old underground water reservoir offers a more industrial kind of tranquility.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

A local landmark that has become a hub of graffiti and urban exploration.

First a horse rendering plant, then a 19th century landfill, this beach is full of glass from thousands upon thousands of broken bottles.

An eerie, derelict amusement park in Berlin.

This Parisian fountain is a little bit fantasy and a little bit nightclub.

This South London cemetery holds the remains of more than 15,000 people.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

A New Zealand couple's shell-adorned home living room, now on display at the Canterbury Museum.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

Known for the tunnel that leads visitors to the water.