A plaque immortalizes the spot where the early American spy said his famous last words: "I only regret that I have but one life to lose for my country."

A memorial to the first person killed by a motor vehicle in the Western Hemisphere.

A humble plaque marks the site where the country music legend was found dead in his Cadillac.

Rising out of a clearing in New Jersey's Pine Barrens is an Aztec-inspired monument to the "Lindbergh of Mexico."

As its grandiose name implies, this wooden dome is unsurpassed in size.

Home of the physician who set the leg of John Wilkes Booth after the Lincoln assassination.

The air force base preserves its scars from the Japanese attack on Pearl Harbor.

The only remaining building in New York to see the inauguration of a president is being slowly overtaken by a grocery store.

These experimental weapons brought World War II to Nebraska as well as 26 other U.S. states.

The remains of a historic plantation nestled in between a parking lot and the rental car return at Reagan National Airport.

Where infamous mobster and leader of Murder Inc. Albert Anastasia made his home.

Three abandoned missile silos are hiding in plain sight behind a suburban development in Maryland.

A bronze plaque at an intersection in Hoboken marks the place where the game of baseball first took shape.

Every drop of D.C. tap water flows through this old waterworks.

A unique gallery chronicles the losers of American presidential history.

A building shaped like the Army Corps of Engineers logo, because why not?

A mammoth pair of Civil War artillery guns abandoned out in the forest.

The garage at the childhood home of Steve Jobs was a hangout for the founders of Apple, even if they never built computers there.

Final resting places of a husband and wife who became famous for their claims of extraterrestrial abduction.

A historic Civil War estate-turned-museum looks back on the Confederate States of America.

The site of William McKinley's tragic assassination is only marked by an underwhelming boulder.

WWII-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers. .

The site where Confederate president Jefferson Davis was defeated has been marked with a bust... that leaves that part out.

The school tested mustard gas for the U.S. Army during World War I.