San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

This rare example of a "tidefall" is a spectacular drop from the cliffs down onto the beach.

Julia Morgan's Moorish-Gothic labyrinth of fountains, trees, natural light and Oakland's notable dead.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.

Canyon walls shrouded in ferns.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

Quite simply the largest tree in the world (by volume).

San Francisco's newly reopened hands-on science museum.

Behind this beachfront shop lies a spectacular, colorful sea cave with an equally colorful past.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

A winding path built in secret on the edge of the continent.

Bridges, terraces, and replicas of historic structures all built of rock and petrified wood by one man.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

This natural marble cave is one of only five national monuments in Oregon.

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

Dramatic river bend surrounds a natural red-rocked pedestal.

Most-visited and most-photographed slot canyon in the American Southwest.

The first American department store, and home to the largest operating musical instrument in the world.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

The body of St. John Neumann and his collection of hundreds of relics, on display in a Philly church.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

World's first "penitentiary," meant to be humane, drove men insane.