Parts of Highway 400 were closed in Barrie after a jackknifed tractor-trailer crashed into a guardrail on Friday.
At one point, the northbound lanes were blocked at Essa Road, while the southbound lanes were blocked at Dunlop Street.
The highway partially reopened during the noon-hour, but some lanes remained closed for guardrail repairs.
No one was injured, OPP say.
Police are investigating the cause of the crash.
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