First nations members from the Robinson-Superior treaty area gathered Wednesday for a march and rally near Nipigon.
It was to demonstrate their concern with the federal government's treatment of First Nations people.
More than 200 people participated in a walk across the Nipigon River bridge to the junction of Highway 11 and Highway 17.
The group included elders, children and people in wheelchairs. Many carried flags or signs.
The event included speeches, prayers, songs and dancing. Among the speakers were First Nations chiefs, including Ontario Regional Chief Stan Beardy and Anishinabek Nation Grand Council Chief Patrick Madahbee.
Ontario Provincial Police were on hand to monitor traffic, which was impeded until vehicles were allowed to proceed along one lane.
Earlier Wednesday the chief of the Red Rock Indian band said she hoped the public would be patient with the rally.
Arlene Wawia estimated waits could be about an hour, as demonstrators planned to educate people about the Navigable Waters Act, as well as hand out information leaflets and bottles of water to motorists.
"This is not only a First Nations thing. It affects everybody in Canada," she said. "Maybe it won't affect us, but what about your children and your great grandchildren?"