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

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

The loneliest island in New York.

A long abandoned hospital building on the outskirts of NYC.

Home to the infamous "Typhoid Mary" and the worst loss of life in New York's history prior to September 11, 2001.

A once grand hotel is being retaken by the wilderness it once capitalized on.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

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

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Gorgeous cave resemble a winter wonderland.

Upside-down trees serve as natural flower pots in this hanging garden of Alaska.

At the center of an island in the middle of the Indian Ocean is a deep chasm ringed by tall waterfalls.

An island in the middle of a lake, in the middle of a volcano, in the middle of a bigger lake, in the middle of a bigger island, in an archipelago, in the Pacific Ocean.

A cemetery and the town it served sinks beneath the sea during the volcanic birth of Mt. Vulcan.

Human ancestor’s 3.6 million year-old footprints.

Home to nearly a third of the world's mud volcanoes, Azerbaijan is home to a messy, bubbling, and sometimes explosive landscape.

This volcanically volatile island town is home to an abandoned series of tunnels left by the Japanese during WWII.

This active volcano's siren song to suicide jumpers forced authorities to build a fence.

Take respite inside this jaw-dropping church while climbing the volcano where Georgia's Prometheus was once chained.

Five mile wide circular ring of rock in the Russian Far East is a curious geological oddity.

A salty cave excavated by elephants and the location of a deadly disease vector.

An abandoned whaling station on an active volcano offers hot springs in Antarctica, surrounded by ruined giants of industry.

The remains of this ancient fortress atop a manmade hill look as though they were built into a volcano.

In this historic region, homes and churches are carved into ancient volcanic rock formations.