Police in the Outaouais say a middle-aged couple suffered serious injuries after their snowmobile rolled several times on a trail in Quyon.
It happened near Highway 148 at about 10 a.m. on Saturday.
MRC des Collines say the two were flung from the vehicle and the woman's helmet was cracked by the force of the impact.
Both are expected to survive.
Police say both speed and a poor reading of the trail conditions played roles in the crash.