The San Gabriel Mountains Trailbuilders (SGMTB) is an all-volunteer, 501(c)3 non-profit public service organization dedicated, to constructing and maintaining hiking trails in the San Gabriel Mountains Angeles National Forest (San Gabriel Mountains National Monument) in Southern California. They were founded in 1984.
The primary efforts which the Trailbuilders perform involve hiking and nature trail restoration, repairs, and maintenance within the Crystal Lake Recreation Area, and the Mount Baldy area, and along the East and West Forks of the San Gabriel River. We perform other work within the Angeles National Forest as needed and scheduled by the U. S. Forest Service, including installing signs at trailheads, building foot bridges, repairing damage to Visitor Centers, removing spray paint vandalism, and other activities which are requested, however trail work consists of 90% or more of what the Trailbuilders do.