An overlooked and unassuming engineering marvel.

A famous alternative culture epicenter and where Joplin serenaded young hippies.

A monument to the love people have for their pets.

San Franciscans leave gifts and messages for the magical beings that live behind the tiny, mysterious door installed on a tree in Golden Gate Park.

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

Nursery with extensive collection of flesh-eating plants operated by the author of "The Savage Garden."

This hidden amusement park is a magical escape for kids and kids-at-heart.

This abandoned boat was left in place thanks to its rotting beauty.

This quirky roadside attraction dives into the many theories surrounding North America's most infamous hairy cryptid.

A giant chess set, minus the psychedelic drug trip.

Come for the records, stay for the retro pinball machines.

A burnt orange monolithic dome structure perched on a hillside near Interstate 280.

The most beautiful Taco Bell in the world even has surfboard parking.

Travelers exchange letters with woodland creatures at this mini post office.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

An amazing collection of fantastic reptiles, amphibians, spiders, and insects.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

An invitation-only museum of items natural and bizarre, arcane and exotic.

The best place in the park to test out your throwing arm.

A quiet nook at the top of a little-known hilltop park named after California's first poet laureate.

San Francisco's oldest operating hotel, with a Victorian atmosphere and a "haunted" fourth floor.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.