Be(w)ar(e) the moat around this historic Czech castle.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

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

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

The "Great Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

Abandoned 19th century homes once occupied by naval officers, soon to be demolished.

This metal eagle one of the final remnants of a newspaper that wanted to keep Brooklyn to Brooklyn.

This beautiful Brooklyn monument over a crypt memorializes a grim and largely unknown story from the American Revolution.

Michael Jackson got Bad and Crocodile Dundee walked on heads in this iconic Brooklyn subway station.

The only surviving sidewalk clock in Brooklyn.

The gilded vestiges of a sterling department store can still be found in a Brooklyn shopping center.

Built hundreds of years ago this downtown iron barrier once protected a much despised king.

The rough and tumble president's childhood home displays the shirt he was once shot in and the speech that saved him.

New York City's only preserved family home from the 19th century.

This innocent-looking townhome is actually a subway exit.

The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

Ride the subways of yesteryear.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

The very first subway station in New York City is beautiful, decked out in chandeliers, and ... abandoned?

This Chase branch is an homage to Old Hollywood.

Hidden in one of the skyscrapers on Bunker Hill, this museum features an 1895 stagecoach and peers into California’s gold-lined history.

The mall's looks were inspired by the cowboy extras who used to meet up—and cause real trouble—at this Hollywood hub.

This opulent hotel has been visited by Spider-Man, Charlie's Angels, and the Ghostbusters.