We just returned from 11 nights (!) at Killarney Provincial Park, which is just north of the Georgian Bay on the North Passage of Lake Huron. We treat this trip (our second of hopefully years to come) like a retreat -- lots of silence, lots of quiet -- and we're totally in love with the place.
It's got a well-kept, thoughtful campground -- so much different than the parking lots we suffer here in Michigan. But more, the geography is something special, with amazing pink granite islands for kayaking in the Georgian bay, and amazing inland lakes with quartzite cliffs -- white rocks with an amazing overlay of fall colors. There's fantastic kayaking (rated some of the best in eastern NAmerica) and great hikes of various levels. The town of Killarney is a working marina, and Herbert's Fisheries has some pretty good fish and chips to prove it.
We've gone now two falls in a row (a two day drive for us) -- and the long slog is totally worth it. It's way more picturesque than the Boundary Waters, which was an old haunt, and the hiking options are far better -- so if it's too windy to get out in the boats, there's a hike somewhere to make up for it. That said, we are very crowd-averse and I can see where summertime would be very busy and probably very different, with a lot more noise. I'm told the place books up completely (4.5 hours from Toronto and about an hour south of Sudbury). But in fall it's quiet and serene -- went out several times in our kayaks and had entire lakes to ourselves, complete with bear/cubs running along shore, "following" us as we paddled quietly down the main channel.
If you go, check out the Trout Lake segment of the campground, where the sites are spacious and secluded. There's also a radio free section with stunning sites on the coast of Lake George (though if the wind is blowing the right way, those sites tend to get battered).
Note that alot of the lakes in the area really got hammered by Sudbury's historic mining/smelting operations -- remember the acid rain of the 70s? This was pretty close to ground zero. Many of the lakes are still recovering (the quartzite rock is apparently more acidic to begin with, so it was like a double whammy) -- some lakes still have virtually no aquatic life, but as a result they're super clear, you can see WAY down. And in all cases, things are slowly recovering, which is encouraging.
Yet another reason for you Canadians -- and for us Americans -- to give thanks today