Los Angeles County sheriff's deputies responded to East Fork Road in Azusa around 12:15 p.m. A resident in the area had called authorities after finding the body while they were on a walk.
When deputies arrived, the woman was found in a culvert adjacent to a roadway turnout. She was pronounced dead at the scene and appeared to have suffered blunt force trauma.
No suspect information was available.
The investigation is ongoing.
Anyone with more information was urged to call the L.A. County Sheriff's Department's homicide bureau at (323) 890-5500. Those wishing to remain anonymous may call Crime Stoppers at (800) 222-8477.