A wildland fire near Donner Summit threatened homes and shut down busy Interstate 80 before being contained at 100 acres.
The fire broke out shortly before 2 p.m. Wednesday and the interstate was closed a short time later.
It reopened about 5:30 p.m. after westbound traffic had backed up for miles.
Hundreds of homes were in the area of the blaze, but no evacuations were ordered and engines were positioned to protect structures.
There were no injuries.
By evening, about 300 firefighters were attacking the blaze with 37 engines, six air tankers, four helicopters and two bulldozers.
In the early evening, winds calmed.
"That allowed us to get ground crews into the area and attack the fire," fire spokesman Daniel Berlant said.
He would not speculate on a cause.
Downed power lines were reported in the area around the time of the fire.
Tractor-trailers parked along the side of the highway.
Other vehicles pulled off at the California 89 interchange and used local
roads to get around the fire scene.
"I saw everyone else turned around, so I just turned around too," said Lee Vymetal of Reno.
"I wasn't going to get through, and if anyone is trying to use westbound I-80, they're not going to get anywhere."