An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

The official atomic museum of the United States explores the explosive and productive history of a much maligned energy source.

A museum dedicated to the alleged Roswell Incident.

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.

A world-class observatory in the California desert.

One of the few remaining carousels built by master amusement park carver Charles I.D. Looff.

One of the largest trees of its kind in California.

North America's largest accredited model railroad museum.

Built for an exposition in 1915, these horticultural displays have stood the test of time.

An extraordinarily ornate museum in San Diego holds wondrous anthropological treasures.

The world's largest outdoor organ is played weekly by one of just two civic organists in the U.S.

The freeway that never was.

An inconspicuous footbridge beloved by San Diego locals.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

Every weekend, people gather here for a brief chance to see their loved ones on the other side of the United States–Mexico border.

A large sculptural artwork and garden in Escondido, California.

Take a leisurely ride on a 1906 cable car or a 1907 steam locomotive.

This dark, quiet forest on the outskirts of San Diego is dense with rumor and lore.

The overgrown ruins of a once thriving World War I-era copper mine.

This large collection of tiny things revels in the art of fine machinery well made.

This unique sanctuary invites you to interact with the beautiful birds.

These unusual houses look like giant boats that washed ashore on a residential street.

What began as an illegal art installation has become a symbol for unity, ocean awareness, and coastline preservation.