A transport truck rollover forced the closure of the westbound lanes of Highway 401 near Comber for four and a half hours.
The rollover was first reported shortly after 7 a.m on Wednesday.
OPP closed the 401 westbound between Comber Side Road and County Road 31.
The section of highway re-opened around 11:30 a.m.
Police have not said if anyone was injured in the rollover.