Highway 17 was reopened just after 2:30 p.m. Tuesday after poor road conditions hampered travel on the north shore of Lake Superior for much of the day.
Ontario Provincial Police said there were many transport trucks stuck on hills. Road crews were working to clear and sand the highway.
OPP initially closed the highway eastbound at Terrace Bay and westbound at Marathon but subsequently extended the affected section to Nipigon following a collision involving two tractor trailers.
Eastbound motorists approaching Nipigon were re-routed to Highway 11.
Snow-removal contract extended
In a related development, the Ministry of Transportation has extended one of its highway winter maintenance contracts in the northwest because of this month's wintery weather.
The ministry asked TWD Roads Management to keep its full fleet available for an extra week.
TWD maintains the highways from around Upsala east to White River.
Typically the MTO contractors are required to keep a full complement of staff and equipment only until April 22.