San Francisco best in October, often some of the best weather.
If you google alltrails … or fix the link
www.alltrails dot com/us/california/san-francisco
It shows the many trails in SF. There is also the Bay Area Ridge Trail loop that has many miles of off road hikes accessible by bus.
That said, we spent a week in San Diego in January (bowl game) and had a great time hiking and riding the electric scooters. There were some nice hikes accessed with busses, but some were just short hikes . Depends on if they mean HIKE hikes, or walks around nice scenery.