One New Hampshire alleyway has become home to a public gallery of feline art.

This riverfront statue honors the inventor of the first video games ever sold.

A gravestone marks where a man's lost limb was laid to rest.

Site of an escape, ten murders, and some scalpings.

A strange, heartwarming, decades-old declaration of love on a New Hampshire roadside.

One of the earliest—and most commonly forgotten—acts of rebellion against English rule.

This former lieutenant governor's home is brimming with curiosities.

These banned cigarette vending machines now sell little pieces of pocket-sized art.

James Turrell's total color immersion art installation, hidden on the top floor of a luxury handbag shop.

Thirteen trees representing the original thirteen colonies were planted with soil from historic Revolutionary battlefields.

A psychedelic labyrinth on the San Francisco bay.

At night, a grove of towering redwood trees growing through the pavement block out all light from the so-called “Dark Park” of Madrone Avenue.

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

Where the writer penned his famous story about a jumping frog.

A cozy bookstore is tucked within an old gold mine shaft beneath the cafe and ice cream shop.

Hidden beneath a lake for decades, this brutalist mine has now emerged from beneath the receding waters.

The old Niles Canyon Aqueduct in the San Francisco Bay Area is a bemusing and secret trail through nature for wayward travelers.

Early prototype for Frank Lloyd Wright's Guggenheim.

An art supply shop holds the secrets of this quiet neighborhood's raucous Barbary Coast past.

A large instrument played by the wind.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

Masterful ceramic fountain and map of the Pacific Basin.

A 140-year-old castle with underground caves hidden in San Francisco.

Condemned US Navy seaplane control tower turned officers’ club sits atop Yerba Buena Island.