Total SF hosts Peter Hartlaub and Heather Knight head to Golden Gate Park to announce their new audio tour of the park, "Secrets of Golden Gate Park: gunfire, graft and a 90-year-old fish." In this episode Knight explains why the park is distinctly San Francisco, Hartlaub shares some history and they introduce the new tour, which operates on the VoiceMap app and uses GPS technology to give a seamless audio tour through the outdoors. The 2.6-mile hike, on the 49 Mile Makeover route created by Knight and Hartlaub, visits the Conservatory of Flowers, AIDS Memorial Grove, Stow Lake, California Academy of Sciences and lesser known spots including the former Sweeny Observatory and Monarch Grove. It's fun and affordable — and Chronicle subscribers get a big discount. Learn more and sign up at sfchronicle.com/audiotours Produced by Peter Hartlaub. Music is "The Tide Will Rise" by the Sunset Shipwrecks off their album "Community" and cable car bell-ringing by 8-time champion Byron Cobb. Follow Total SF adventures at www.sfchronicle.com/totalsf Learn more about your ad choices. Visit megaphone.fm/adchoices