While checking out KTVU’s Hiking Guide I came across this one I’ve never even heard of: Sibley Volcanic Preserve.

In the bowels of an ancient volcano where crude labyrinths materialized, humans and furry beasts wander through forests of eucalyptus and pine, exploring these strange convoluted paths…. This reads like the start of a supernatural novel, but it’s just a description of the daily routine at Sibley Volcanic Preserve. Sibley was one of the first three preserves created by the East Bay Regional Park District, founded way back in 1936. The preserve’s focal point, Round Top, was once a volcano. Ten million years or so passed, and surrounding Orinda Formation rocks eroded away, so when the land was quarried, cross sections of the caldera were exposed, as well as other volcanic features including basalt dikes and breccia outcrops. The labyrinths appeared in the scooped out quarried areas more than 10 years ago. Unlike a maze, which has a different entrance and exit, a labyrinth shares one path into and out of the center. They have been used traditionally as a means for meditation, and visitors do walk the labyrinths at Sibley hoping for spiritual succor.

Jane Huber of bahiker.com provides the text for the guide, which points to many of the usual suspects around here.

Here’s the East Bay Regional Parks’ Sibley page