The remains of a 19th century spring, and the site of an infamous unsolved murder.

Edgar Allan Poe's old dorm is now a shrine to the author's legacy.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

The history of radiation is on safe display at the foot of a radiation science laboratory.

The notorious headquarters of a corrupt political machine.

The saddest little diner in New York.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

An unsettling painting of three faceless sisters that is surrounded by history and legend.

A submerged archeological park still holds the wonders of a Roman Sodom.

An urban forest overtakes what was the greatest failure of utopic urban housing.

Puzzles within puzzles hide a golden treasure in this hedge maze.

Mosaics, storks, and brothels—this ancient city has it all.

This massive subterranean fissure is known as the "underground Grand Canyon."

A castle built for love, and abandoned due to heartbreak.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

Home to the most complete dodo remains known - one head, and one foot.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

This half-finished "city of toys" was almost Italy's own Las Vegas.

The abandoned hospital whose elaborate ghost stories cover up the dirty truth - an uneventful sanitation issue and other mundane reasons for its demise.

A museum designed by and dedicated to P.T. Barnum in the town where he is buried.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

The end of the 4 Line is also the end of the line for 300,000 souls in one of NYC's most illustrious cemeteries.

A long abandoned hospital building on the outskirts of NYC.

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