Take a look at Lake Superior Provincial park, it is a couple hours north of Sault Ste Marie on the Trans Canada highway. The drive from Sault to the park is amazing and the park is also amazing, isolated pebble beaches to walk on, excellent hikes in the hills, some amazing native pictographs on the water and some beach front sites to watch the sun set on Lake Superior. It is also far enough north to avoid the party weekend crowds. I have been to a lot of provincial parks in Ontario and it is one of my all time favourites. Once you get north of the Sault, it is the real north, so not a lot of food choices.