A unique collection of more than 250 rocks and minerals located on a university campus.

This shifting North Carolina sand dune is an odd little desert surrounded by oceanic forest life.

A stunning garden filled with fantastical environmental folk art and sculptures.

One of the few surviving original NASCAR dirt-track speedways.

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

The most decorated dog of World War I is preserved in the Smithsonian.

This taxidermy horse was a Civil War hero.

Perhaps the most scandalous statue of America's first president.

This massive airship factory is so large that it has its own indoor weather.

This steamer is known as "The ship that built Cleveland."

Marvel at this turn-of-the-century masterpiece that has been turned into a rather stately supermarket.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

This spectacular public market has got meat, fish, vegetables, baked goods, and enough kielbasa for a lifetime.

Rare recess caves fill this unbelievably beautiful Ohio park.

An old train trestle re-imagined as an Egyptian obelisk.

The world's largest fire hydrant is supposedly tornado-proof.

This psychedelic tromp l'oeil seems to be beckoning drivers to crash into a wall.

This titanic steel chain linking two buildings was installed without permission but instantly beloved.

A handful of beehive kilns are all that’s left of a historic brick-making empire.

The scene of the largest surrender of Confederate troops at the end of the American Civil War.