A monument to a Native American leader who was known for never breaking a promise and met his end after signing a deal with white settlers.

Pennsylvania's own Roswell-style UFO mystery.

Steepest flood safety railway in the entire world.

Memorializing an American tragedy of massive proportions.

This museum inside a museum tells the story of London's timepieces.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

This smaller cousin of the Forbidden City has gone from ancestral sacrifice to tourist's whispers.

Hot Doug's "Hot Dog" Stand.

These chunky stone towers out in Lake Michigan are the key to Chicago’s drinking water.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

Golden and naked, the figure that was once the highest point in New York is all that remains of the second Madison Square Garden.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

Before founding the American Red Cross, Clara Barton had a tremendous humanitarian impact by locating thousands of missing soldiers.

An easily overlooked memorial to a Ukrainian famine-genocide that killed over 4 million people.

Need a hardcopy of the 50-title Code of Federal Regulations? This is the place.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.

This crumbling medieval basilica once attracted pilgrims by the thousands to collect a miraculous dust that formed above the saint's tomb.

The remnants of a creative early method of wildfire prevention.

One of the oldest of its kind.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

The first bell ever cast in Boston was cast by Paul Revere...and sounded terrible.

This area was once known for being a lawless haven for rough-and-tumble sailors, earning the maritime-themed nickname "the black sea."

One of the indelible moments of the American Revolution took place at this location.