Political events in the Bay Area Friday Bernie Sanders: Sen. Bernie Sanders, independent-Vt., speaks at a California Nurses Association-sponsored rally in favor of a single-payer health care system. The event begins at 1 p.m. Friday in the Yerba Buena Gardens esplanade, off Mission Street between Third and Fourth streets in San Francisco. Saturday Peace in the Park: Features speakers, live music, poetry, visual artists, tai chi, hatha yoga and “meditation experiences where individuals can explore a variety of ways to unplug, unwind, tune in and connect in peace.