The sole lane of Highway 39 that leads into the San Gabriel Mountains reopened Monday afternoon after it was closed due to a high volume of Labor Day vacationers, authorities said.
The Los Angeles County sheriff's mounted units made the call to shut down the lane, but it's unclear what time the closure began, according to Sgt. David Grall of the San Dimas Station.
"There was an extreme influx of vehicles and emergency vehicles couldn't maneuver around them," Grall said.
The road was eventually reopened about 5 p.m., Officer Jennifer Cassidy of the California Highway Patrol said.
Other factors such as no vacancies at campsites led to the decision of closing access, Grall said.
Glendora Mountain Road and Glendora Ridge Road are scheduled to reopen Tuesday morning. The two roads were closed to reduce the risk of brush fires over the Labor Day weekend.
- City News Service, Local Editor Hazel Lodevico-To'o contributed to this report.