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

This black shoreline is made up of exploded lava particles.

This "Alaska-style" billboard is over 100 years old.

A historic area for shopping and dining in Ketchikan's former red-light district.

This historic collection of Native Alaskan artifacts was resurrected through a partnership between the WPA and tribal artisans.

The mounds on this coastal archaeological site reveal the history of the land’s first inhabitants.

Recently celebrating its 25th anniversary, the garden opened in September 1997 to celebrate the men and women who have had the greatest impact on Key West.

One of the oldest, tallest, and most haunted lighthouses in America.

Dedicated to the victims of one of the deadliest hurricanes to strike the United States in recorded history.

Near the ruins of a Civil War coastal fortress lies the only known African refugee cemetery in the United States.

A historic presidential getaway on the continental United States' southernmost island.

Location of a reliquary containing bone fragments of 18 saints.

"We Seceded Where Others Failed."

An idyllic swimming pool tells the tale of Hemingway's trouble with women.

The smallest post office in the United States is no bigger than a broom closet.

The highway's southernmost spot is a beloved local attraction.

The birthplace of American international flight service has been turned into a celebrity's microbrewery.

This spiny beast guards an artist's village while vying for the title of largest lobster in the world.

A building so large that it has its own weather.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

Pensacola's UFO home has withstood many hurricanes—just as the experimental 1960s design intended.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

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

A monument celebrating the idea of reaching inaccessible places.