America's most famous piece of self-built architecture.

A World War II evacuation tunnel turned into a history display of Croatian state and people.

One of Frank Lloyd Wright's greatest—and favorite—architectural masterpieces was almost lost.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

Once the largest public hospital for the mentally ill was also surrounded by controversy.

Tucked away amidst some of the most famous addresses in the world is New York's only fraction of a street.

This water tower has been a staple of the Rochester skyline since 1931.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

Software company Epic Systems has created one of the strangest and largest workplaces of all time.

This otherwise innocuous bodega was once the headquarters of the most feared assassin's guild in American history.

The oldest surviving presidential residence in the United States.

Paranormal activity on the great lakes.

Giant six-pack could provide one person a six-pack a day for 3,351 years.

A metal ring in the middle of the road marks the exact spot where the Soviet satellite crash-landed in 1962.

This nearly 200-year-old restaurant's history includes an exiled French prince, JFK, and a very hungry Daniel Webster.

An allegedly haunted testament to a local businessman's desire for status, posterity, and charity.

Europe's official "zero-level," the equator of elevation.

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

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

A museum celebrating the self-taught artist-environment builder.

Abraham Lincoln's vice president took his last breath here on July 4, 1891.

A bizarre house filled with an astounding array of collections.

An unusual number plate signifies the building's saucy past.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.