This ancient market is often referred to as the oldest shopping mall in the world.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

The world-record holder for the longest bridge stretching continuously over water.

The largest wooden building in the world now houses a fascinating collection of aircraft.

The inventor of the Coney Island hot dog rests in a grand mausoleum in Brooklyn.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

A tunnel with windows, so you don't miss out on the impressive views.

A rare chance to get up close and personal with a 13-mile ribbon of ice near downtown Juneau.

Elevated freight railway turned wildly successful urban park.

The most beautiful Taco Bell in the world even has surfboard parking.

This bridge over the River Cuale leads to a neighborhood that was once an escape for Hollywood's elite.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

A spectacular cave and a beguiling lake.

This relatively recently abandoned brewery is a tragic reminder of the continuing effects of Hurricane Katrina.

A little piece of Paris in the sultry south of the U.S.

A snapshot of the city's fascinating voodoo culture.

This 19th century train workshop is a treasure trove of railroad history.

In the middle of downtown Brooklyn lies a 165 year old secret hidden right below the surface (closed to the public indefinitely).

The abandoned husk of a mental institution that failed to save a Jazz Age icon still sits nearly unchanged.

This abandoned cemetery is crumbling into ruin, exposing the artifacts and bodies buried there.

Deep under Manhattan is the largest construction project in city history. So far, the project has taken the lives of 23 workers, or "a man a mile."

This beautiful building in the heart of Manhattan's Financial District was empty for decades.