Passerby notified authorities after they found a man lying in the road near the campsite at about 5:40 p.m. Thursday.
When investigators arrived, they found the victim with gunshot wounds. He was transported to a nearby hospital where he was pronounced dead.
The victim's identity was not immediately released.
If you have any information regarding this case, you're urged to contact Los Angeles County Sheriff's Department's Homicide Bureau at (323) 890-5500.