See Photos of Caitlyn Jenner's Manager's Fatal ATV Crash in Malibu

Caitlyn Jenner's longtime friend and manager, Sophia Hutchins, died in a tragic ATV accident Wednesday morning -- and footage of the crash site has surfaced.

TMZ broke the news ... Sophia was pronounced dead at the scene in Malibu after she swiped the bumper of a vehicle with her ATV and was consequently thrown 350 feet down into a ravine.

A KCAL News chopper debuted footage of the aftermath of the crash on Wednesday before Sophia was identified ... showing her blue ATV resting atop an upside down vehicle that had previously crashed in the same spot.

Sophia was the only casualty in the accident.

TMZ has reached out to Caitlyn for comment ... so far, no word back.

The retired Olympian and Sophia had been by each other's sides since 2015 ... and Sophia even joined Caitlyn in several episodes of her E! docuseries "I Am Cait" as her manager.

Sophia previously credited Caitlyn with giving her the confidence to transition while attending college at Pepperdine University.

After graduating, she founded a sunscreen brand, Lumasol.

She was 29 when she died.