Concrete strongholds stand guard over the Golden Gate.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

Mining town from the late 1890s, once home to Calamity Jane.

Built during the Scottish boom in the oil industry, the village was never inhabited.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

A New England ghost town features a trail of boulders etched with intriguing life lessons.

The ancient settlement attracts tourists from all over looking to learn about the Chinese vision of the afterlife.

Once connected to the outside world by a single train track, this ghost town is looked after by the National Park Service.

Population: 1.

An abandoned bait shop with a front lot filled with storage boxes.

Toxic waste disaster that founded the Superfund program.

Disney's abandoned animal island is now an overgrown ruin that was almost the coolest attraction ever.

A small abandoned and abused cemetery that has become a magnet for ghost hunters.

The museum moved on, but the diorama remain.

The music is over at the Ballhaus Riviera Ballroom, but the ballroom remains in haunting disrepair.

The mouldering remains of a disgraced British children's icon are hidden in the brush of a public park.

A former seaside jewel built for the everyman is now simply a neglected art deco fortress.

This abandoned seaside fortress is now simply an imposing ruin being taken back by nature.

The remains of an idyllic small town built for the film 'Big Fish' still stand around a rundown main street.

The site of one of Japan's very few American occupations during World War II still holds the relics of a roundly disastrous campaign.

When Croatia became independent of Yugoslavia, the splintering governments left behind these concrete tunnels.

Formerly Yugoslavia's "forbidden island," this sleepy little city still holds the abandoned remains of military strongholds.

This Sumatran root bridge took almost 30 years to knit itself together.

This tangled English forest looks like something right out of a fairytale.