Historic psychiatric asylum and most-filmed location in the Great White North.

The remains of the furnace and iron works that produced the massive Hudson River Chain still stand in the woods of New York.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

The ruins of an ancient temple to the Aztec wind god discovered in the middle of a metro station.

The last SR-71 ever constructed.

The original "capsule building" is a masterpiece of Metabolist architecture.

An abandoned asylum where patients have been forgotten but their possessions remain.

Tucked away atop a quaint Alabama pharmacy is this tiny display of antique medical tools.

Pensacola's UFO home has withstood many hurricanes—just as the experimental 1960s design intended.

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.

A tiny memorial for the year the Connecticut River almost destroyed New England.