This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

A century-old network of freight tunnels underneath the city's historic business district.

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

Military and first responders can test their skills in a Foggy Bottom mock station down in Georgia.

Walk the whole Mississippi River!

In the St. Francois Mountains in the Ozarks at 1,772 feet above sea level, Taum Sauk Mountain is the highest (and possibly oldest) peak in Missouri.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

This three-mile concrete levee in Pueblo, Colorado was transformed into the world’s longest painting.

The highest bridge in America was built for an almost unnervingly small amount of money.

Despite being one of the most photographed vistas in the Rockies these twin peaks are rightfully known as the "Deadly Bells."

A research lab and hands-on museum where visitors can experiment with retro technology.

The clock that sets them all.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

An innovative local park built from an abandoned sewage treatment plant.

A technicolor place of worship for Elevationists.

Where scientists keep miles of very valuable ice from Antarctica and Greenland from melting.

See six states, pickled freaks, rocks, and antiques.

A rainbow-colored house promotes LGBTQ rights across the street from the Westboro Baptist Church.

The famous greeting card maker owns a collection of paintings by the famed surrealist.

A piece of John the Baptist in the American heartland.

The first car-centric shopping plaza in the U.S. brought a little bit of Spain to downtown Kansas City.

This unconventional used book store was once in the news for the surprising act of burning books.

Step back in time at this 1950s display home, built to showcase once cutting-edge electric amenities.

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.