The clock started ticking when a mountain biker riding on an illegal trail in Annadel State Park hit a root and crashed, breaking his neck.
As word of the accident crackled over emergency radios, Bennett Valley firefighters and a state park ranger jumped into pickups packed with rescue gear.
"Time was of the essence," Bennett Valley Fire Lt. Travis Browne recalled. "We just needed to get paramedics to that patient."
But as the light began to fade, they did not know where to go.
Tony Lamperti, 47, of Sebastopol and his group of mountain bikers had been riding on an unmapped trail near Bennett Peak. Browne eventually found Lamperti in an area not well known to firefighters, inaccessible by helicopter and barred to park visitors.
"It was one of those worst-case scenario medicals where we're all trying like mad to get there," State Park Supervising Ranger Neill Fogarty said.
The March 17 effort to find and retrieve the injured man brings to focus an enduring problem for emergency responders and environmental stewards: people who head into prohibited and fragile areas of the park.
Exploring off-trail can not only damage park habitat, it can result in long delays for emergency aid when accidents occur, said Bert Whitaker, Sonoma County Regional Parks operations director.
"That incident really did showcase safety issues with illegal trails and people using them," said Whitaker, whose agency is working with state parks to manage Annadel. "They are not on a park map. There are not (trail) names recognizable to responders out there."
Lamperti praised all those who helped get him out of the park, although he declined to discuss why his group went off official trails or what he thinks of the matter.