Where hills of dirt conceal the burial ground of one of the most powerful ancient Native American societies.

Bronze statue marks the spinach capital of the world.

This monumental Jesus is often referred to as "Our Milk Carton With Arms."

This haunted hotel built on natural springs once served as a hospital for a quack doctor promising a cure for cancer.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

Sometimes called the “Little Golden Gate," this bright yellow structure is the last driveable suspension bridge in Arkansas.

From a canyon-like gorge, more than 20 million gallons of water emerge every day, while a smaller spring drips down, creating the illusion of an endless, gentle waterfall.

A mid-century telephone booth still stands, now a long-distance relic of the past.

The first commercial phone line west of St. Louis was installed thanks to a group of Cherokee businessmen.

The granite monument is engraved with the image of the talking horse's head coming through a barn door.

The largest protected conservation area in the Ozarks—a region that stretches into northern Arkansas and southern Missouri.

A whimsical tower with a spiral staircase, inspired by the Space Age and the Möbius strip.

The only fully-realized skyscraper built by the famed American architect, Frank Lloyd Wright.

An oil baron's wild paradise and the winner of an ill-fated air race.

An acoustic anomaly with a mysterious cause sits in the heart of Tulsa.

Tulsa's historic skyscrapers define the oil boom era of Art Deco construction, and are known for their ornate arched lobbies.

Standing at 21-feet tall, this space cowboy adds to the legacy of Route 66's muffler men.

This 1930s-era Route 66 Tulsa landmark was moved, restored, and filled with neon.

One of the best examples of Art Deco architecture in the United States.

The fifth tallest statue in the United States is a shirtless monument to the oil worker.

The collection is housed in an exquisite mansion that makes you feel like you've been transported to an Italian villa.

These massive mitts are made of 30 tons of devotional bronze.

Nature's biggest mammal swims in landlocked Oklahoma.

A detached cement mixer has been transformed to resemble a relic from some obscure NASA mission to Oklahoma.