You can spend the night as an honorary lighthouse keeper in this quaint, historic beacon.

A drab two-story office space in Delaware is a hidden tax haven for Hillary Clinton, Donald Trump, and over half the Fortune 500 companies.

These old doors are covered in the signatures of Rehoboth Beach artists dating back to the 1930s.

The oldest surviving presidential residence in the United States.

America's smallest national park site is the former residence of exiled Polish national hero Thaddeus Kosciuszko.

Current docking place of the SS United States, the fastest transatlantic ocean liner.

Dr Barnes' $25 billion private collection of art and arboretum.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

This recently rediscovered Civil War-era submarine was the first to ever sink an enemy ship.

Charleston's historic city jail once held everyone from pirates to Civil War POWs.

This small memorial is almost as well concealed as Smalls himself was on the night he sailed to freedom.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

A small but immensely extravagant palace built by the "Night King."

A lonely memorial to the Challenger Space Shuttle, honoring the astronauts who died in 1986.

One-of-a-kind museum inside the first Boeing 747-400 ever made.

This lookout tower built in the 1930s is now an in-demand cabin with what might be the best view of the Seneca State Forest.

A memorial honoring those who perished in one of the worst construction disasters in U.S. history.

Once connected to the outside world by a single train track, this ghost town is looked after by the National Park Service.

A secret rendezvous spot where John S. Mosby and his Rangers would meet to divvy up their loot after raids.

Remnants of a wall built to separate Black residents of Hall's Hill from a newly built subdivision are a grim reminder of segregation in 20th-century Virginia.

This eye-catching sculpture of rural life seems a bit out of place at a suburban intersection in front of a car dealership.

A small and somewhat hidden memorial to 68 local veterans of the Vietnam War.

Named for a Greek oracle that interpreted the words of Zeus, this beautifully-restored manor home was once home to the architect of the Marshall Plan.

This "castle" is actually a limestone and quartz formation hidden along a trail.