Matt Davis-Steep Ravine Loop
Joyce Park stashed this in Camping and hiking
Lots of San Franciscans swear by this route, so it is bound to be crowded during the summer.
The Steep Ravine and Dipsea part of this trail is very narrow and gets crowded fast. There's some kind of running race that happens on this trail every year, and the people training for it are a menace -- especially I imagine in the spring leading up to the race in early June.