The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

Dozens of feral felines rule a segment of Hollywood's only graveyard.

The "world's biggest dinosaur" once housed a creationist museum in its abdomen.

Where a great scandal unfolded with a famous female revivalist at its center.

A second generation sun-powered marvel lights up the night.

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

An offbeat angle on the ocean viewed through an antiquated lens.

One of the first skyscrapers in Santa Monica, and a famous getaway for the Hollywood elite of then and now.

In one Santa Monica parking lot a mushroom cloud made of chains heralds a message of peace.

Giant origami crease patterns engraved in Santa Monica intersections may even be visible from space.

Perhaps the most unique of any Frank Gehry design for one simple reason: Gehry himself actually lives here.

On a quiet suburban street stands a peculiarly decorated house covered in mosaics.

A free library to stumble across, one of many placed worldwide if you know where to look.

Memorializing the bravery of one young woman facing the monster of her age.

Whether hero or rogue, his silver bullet is said to have taken down the murderous "Beast of Gevaudan."

What looks like a normal building is really a hollow facade hiding a subway vent.

A Parisian boutique devoted to la Sape, the elegant Congolese fashion subculture rooted in European colonization.

Egyptian Revival movie palace abandoned for decades and restored in 2013.

The Sun King's military models, saved from the Louvre.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

Fantastic views and thousands of love locks.

A memorial for a young woman and her ghost, which are claimed to have caused countless deathly shipwrecks.

Carved fountains poignantly placed in parks and in front of special monuments.