A Lake Elsinore man died Tuesday afternoon after falling 75 feet near Sapphire Falls in Cucamonga Canyon north of Upland and Rancho Cucamonga.
Jacob Daniel Hernandez, 19, had been hiking and rock climbing with his cousin when he fell in the popular San Gabriel Mountains location shortly after 3 p.m.
After the fall, his cousin, whose name was not released, managed to call rescue officials despite spotty reception in the canyon.
The two men were off the beaten path, officials said.
"They were trying to get from one waterfall to another, and they took a route that was very dangerous," Rancho Cucamonga Fire Chief Mike Bell said.
The two men had come up into the canyon via the Skyline Road entrance, Bell said.
Paramedics declared Hernandez dead at 4:16 p.m.
The cousin had only a few bruises and scrapes and did not require hospitalization.
"They were climbing up the rock cliff. (The cousin) was first, and Jacob was behind him. He heard Jacob slip," said Cindy Bachman, a spokeswoman for the San Bernardino County Sheriff's Department.
The canyon area, which is filled with boulders and at times a swift-running creek, attracts many visitors who make the 3.5-mile hike into the area.
It has also been the site of numerous injuries and some deaths.
County coroner's officials will perform an autopsy.
The city has taken measures to reduce numbers of people going into the canyon, after social media accounts of the falls have attracted larger numbers of people in recent years. With the increased traffic, residents have complained of trash, graffiti, and crime.
City measures have included parking permits, and signage alerting people to the proper entrance to the canyon at the northern end of Skyline Road. Officials are considering ideas that include more permits, parking meters on Almond Street, and a 7 a.m. to 7 p.m. parking curfew.
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