The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

See massive fossils that are over 200 million years old in northeastern Arizona.

This small interfaith chapel lies not far from the rim of the Grand Canyon.

The Giant Lemon of Lemon Grove.

This futuristic bridge is one of the longest self-anchored pedestrian bridges in the world.

In September 1974, a small group of athletes completed the first modern triathlon event in San Diego's Mission Bay.

Two small markers remember the Alamo's feline protectors.

Legend has it the commander of the defenders drew a fateful line in the dirt with his sword just before the final battle.

Hike the unusual hoodoos and rock formations that form this little-known natural wonder.

This private residence was the template for one of the most beloved television homes of all time.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

One of the oldest producers of hand-folded fortune cookies still uses its original secret recipe.

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.

The first presidential bomb shelter was located in an old vault under the Treasury, connected to the White House via tunnel.

An overlooked memorial honoring the local Washington residents who died in World War I.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

In California, colorful roadside signs remind us all that love transcends borders.

This mostly abandoned shopping outlet is now adorned with beautiful graffiti and murals.

These markers are used to determine the ground stability of the Strip.

For over 20 years, Lil Toot has delighted guests with narrated boat rides between Stearns Wharf and Santa Barbara Harbor, becoming a beloved local legend and top-rated experience for visitors.

View the California coastline (and the home of Barbara Streisand) inch by inch with stunning, government-sanctioned aerial photography.