Smith Moutain, San Gabriel Mountains

Below are some quick facts obtained from the book Hiking Southern California*:
Location: Central San Gabriel Mountains, 10 mi north of Azusa
Trailhead elevation: 3300'
Highest point: Smith Mountain at 5111'
Best time to go: October through May
Trail contact: 909-335-1251
National Forest Adventure Pass required (one per car)

A short description of the hike can be found here.

*This book can be picked up for about $4.50 used on Amazon, which includes shipping.