A cyclist was seriously injured Saturday afternoon in a head-on crash on Trinity Road in Glen Ellen, according to the CHP.

Tristan Humble, 25, of Santa Rosa, was taken by ambulance to the Cal Fire station in Glen Ellen and flown by helicopter to Santa Rosa Memorial Hospital.

The CHP said the accident occurred at 3:55 p.m. when Humble, who was going downhill, drifted into the lane of the on-coming traffic on the steep, twisting road.

CHP Sgt. W. Bradshaw said that two cyclists who were riding with Humble said it was his first time riding on Trinity Road.

Humble hit the front fender of a mini-van and was thrown onto the windshield, suffering major head injuries, Bradshaw said.

No one in the mini-van was injured, Bradshaw said.