Five people were sent to hospital, with one then being transported to a trauma centre, following a crash on Highway 400 southbound in Georgian Bay Township.
Southern Georgian Bay OPP say they, along with paramedics and firefighters, were called to the scene just north of the ramp to Crooked Bay Road around 9 p.m. on Saturday.
One of the drivers was extricated by fire services before being brought to a local hospital where he was further transported to a Toronto trauma hospital.
A 33-year-old North York man was charged with Careless Driving contrary to the Highway Traffic Act.
The southbound lanes of the 400 reopened Sunday morning.
Banner image via Southern Georgian Bay OPP