This is my favorite run in the area, used to run it weekly when i lived in marin.
starts in the middle of town and you run to the trailhead for phoenix lake. dirt path around the lake...up shaver-a fire road...and then a nice rolling hill kind of descent back to the lake and finish back at the cars. The views are beautiful! Trail shoes recommended. Only one water fountain on the way and its not where you'd want it!
Its challenging but absolutely runnable.
Lets figure out some carpools.