Riding from home to Guadelupe Canyon Road which then connects to a lovely dirt trail and goes on the back side of the mountain and behind a large water tank. From there you can then just cross to the other side where there are even more graveling with views of downtown San Francisco and across the Bay to the East Bay and then towards the South Bay.
There is a ranger gate but I rarely ever notice if there is a ranger in it to collect a fee. There are curfews but it's mostly for vehicles. If you decide to ride all the way up to the end of Radio Road, just be careful of cars as they have access to the top of the mountain.