Seattle firefighters helped 84 passengers off the only two trains on the one-mile, 43-year-old elevated line between downtown and the Seattle Center, said Helen Fitzpatrick, fire department spokeswoman. The train had left the Westlake station shortly before the accident.
John Gahagan, who was riding the monorail with his wife and two children, said the collision ripped off the sliding door on their train car and broke a window, showering his children in glass. The children, ages 15 and 11, were not injured.
"We heard a screeching sound -- metal on metal -- and glass breaking," said Gahagan, 50, of Mukilteo, Wash., who added that several people slid off their seats. Still, he said, the crash "wasn't real violent."
"The scariest thing was coming down the ladder," he said about an hour and a half after the accident. "We're fine. Everybody in the car was fine."
Several blocks of Fifth Avenue were closed after the accident, which happened shortly after 7 p.m., Fitzpatrick said.
The Seattle Police Department would investigate the crash, said Officer Rich Pruitt. He said the National Transportation Safety Board would also likely investigate.
The crash occurred over streets where the Seattle Marathon was scheduled to be run on Sunday. Pruitt was not sure whether the marathon would have to be rerouted.
The monorail was built for the Seattle World's Fair in 1962 and has been popular with tourists, drawing as many as 23,000 riders a day. But a years-long fight to expand the system met with sound rejection this month.
Voters had approved a 14-mile system in 2002, but opposition grew after the estimated price more than quadrupled to $11.4 billion. On Nov. 8 voters junked the project entirely, rejecting a 10.6-mile, $4.9 billion alternative monorail proponents had offered.
The line was shut down for more than six months last year, after a smoky fire stranded about 100 riders. No one was seriously hurt.