Highway 26 east of Prineville had re-opened by Friday morning, with traffic congested but moving. Earlier, Oregon Eclipse festival visitors faced 12-hour delays.
Meanwhile a fire prompted officials to close Oregon 242, one mile west of Sisters.
Peter Murphy, with the U.S. Forest Service, Region 4, said the blaze is on difficult terrain.
“There are some rocky areas, big lava flow,” Murphy said. “Beyond that, within walking distance of the highway there’s a lot of dead and downed trees, because it’s managed as a wilderness area.”
That kind of fuel, Murphy said, gives the fire a free path to burn. Tanker jets are in the air to suppress the blaze.
Safety officials say residents of Sisters should prepare for possible evacuation.