At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

The eclectic observatory castle of a 19th-century astronomer and explorer.

Trek into the depths of the cave where 17,000-year-old paintings exist alongside 400-year-old graffiti.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

This black shoreline is made up of exploded lava particles.

The southernmost point in the United States is a beautiful place to look at but a deadly place to wade in.

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

An authentic replica of an Asian temple and garden hidden amongst the natural beauty of Hawai'i.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

A tunnel of hardened lava along Maui’s famous Road to Hana.

A trading post in the North Pole where children send letters.

The king of U.S. high points towers over every other peak on the continent.

Electrical pylon in the shape of Disney's beloved mouse.

St. Augustine's record-setting narrow street was designed to protect against pirates.

The third tallest lighthouse in America once guided author Stephen Crane to safety.

A building so large that it has its own weather.

A vast array of tropical plants collected by a vacationing couple.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

One of many gator theme parks, abandoned in the sugar fields of South Florida.

A tribute to Ponce de Leon's supposed quest for eternal youth.

Town of spiritualists and mediums in Florida.

The scuba diving training facility was named for the steam that rises from the cave's chimney.

Florida might be at its most surreal in this museum devoted to the famed Spanish artist.