Labyrinths, those mazelike structures in which you can figuratively lose yourself, date back to Greek mythology. Typically regarded as places of spiritual energy, meditation, and contemplation, they are said to be facilitated by the twists and turns of the paths and, some say, inherent mystical qualities. For a few who wander them, they are, quite simply, an antidote to stress. Lake Merritt, at Lakeside Park near the children's playground, has an accessible labyrinth. Installed in 1992 as a Public Art Project and based on a labyrinth at the Chartres cathedral in France, it is a simple structure comprising grassy mounds and a dirt path. The mother of all East Bay labyrinths, however, requires a drive, a hike, and a map. In 1980 Helena Mazzariello, a sculptor living in Montclair, created the Mazzariello Labyrinth (sometimes dubbed the "Volcanic Witch Project") in Oakland's Sibley Volcanic Regional Preserve, as an art project. She reputedly used to walk her goats in the labyrinth's quarry area home and would feel a "kind of magnetic force." Look forward to a robust hike and great views getting there. Then chill out.