The crash occurred just after noon on Highway 29 south of Cruickshank Road, according to the California Highway Patrol.
A 73-year-old Clearlake Oaks man was driving his 2001 Chevrolet Corvette northbound on Highway 20 south of Cruickshank at approximately 55 miles per hour, and a 50-year-old Lower Lake woman was driving her 1997 Mercury Mountaineer southbound, also at 55 miles per hour, the CHP said.
For a yet-to-be-determined reason, the Corvette traveled across the double-yellow lines and hit the Mountaineer head-on, according to the CHP report.
The CHP said the Corvette's driver was flown via REACH air ambulance to Santa Rosa Memorial Hospital with major injuries, while the woman in the Mountaineer was taken via Kelseyville Fire ambulance to Sutter Lakeside Hospital in Lakeport, where she was treated for minor injuries.
Both drivers were wearing their seat belts, the CHP said.
Reports from the scene indicated the crash blocked both lanes of traffic, with the highway completely cleared just before 2 p.m.
CHP Officer Randy Forslund is investigating the incident.
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