One-time winter retreats of prolific inventor Thomas Edison and his friend Henry Ford.

Enormous lake at the bottom of a unique cave system.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

This bridge was the birthplace of a unit of measurement based on a fraternity joke.

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

The largest island on the great salt lake is home to curious creatures and strange stories.

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

Three hundred years of preserved Spanish colonial history in San Antonio.

One of the oldest living oak trees in the Southeast.

Holding multiple historical boats and an entire 19th century village, this New England attraction is the largest maritime museum in the world.

Yo, Adrian!

This abstract roadside poultry was saved from demolition by outraged drivers and pilots.

This elaborate towering structure was once famed for its revolutionary height.

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

The modern birthplace of Irish freedom.

Home to the deepest rift anywhere on Earth.

Every day a troupe of pampered water fowl walk the red carpet to their favorite fountain.

A geological mystery on Camelback Mountain.

Giant, friendly pelicans in Central London, the most unlikely of places.

The ancient tomb acts as a calendar that keeps perfect time.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

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

Experience a charming 1930's version of "infotainment."

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.