notes on the indefinite height of the highest point in ontario
But this distinction is rather new. Earlier, Ogidaki Mountain, and then, Tip Top Mountain also held the distinction. Or at least, that's what I've read in several places, like in Not Won in a Day, or Ottertooth, or Hap Wilson's Temagami Canoe Routes. I've never seen the original documents these claims are based on.
Anyways, everyone who claims to have been to the highest point in Ontario has climbed to the knob on which the firetower sits, following what may have been the trail from Scarecrow Lake. I will call this the "firetower knob".
But two kilometers to the north, there is another knob, covered with trees, that looks to be about the same height. I will call this the "north knob". When I was there in 2005, I attempted to determine which point is higher by using a home made sighting-level, as well as the clinometer on my compass.
The tree covered "summit" of the north knob prevented me from determining which knob is higher.
There is no trail going to the north knob and hiking to it would take a couple hours of bushwacking. The two knobs are separated by a deep valley and steep rock faces. A better approach to the adjoining knob would be up a drainage from Smoothwater or a bushwack from McCullock.
So, what about maps? Well, despite the rather dubious history of maps in determining the highest point in Ontario (as described above), I've made the following observations:
The OMB data should be more accurate...it's at a larger scale and has stricter accuracy conditions.
Just to confuse things, the Atlas of Canada lists the height of Ishpatina as a rather precise 693m, but they don't reference a precise source. Google tells me that 2,250 feet (the highest NTS contours in Ontario) is 685.8 metres and 2,300 feet (which would be the theoretical next contour interval) is 701.04 metres. Split the difference and you get 693.42, close to the Atlas of Canada elevation.
I took a WAAS-enabled averaged set of GPS points that put the summit plateau at 692m. There is a small mound (probably of top soil that was cleared and piled during the fire tower construction) that is about 1.5m higher than the plateau.
There's no sign of a survey monument on the ridge, so it's likely that no survey has ever been done of the area. Strange, given the fact that it is the "roof" of Ontario!
Chrismar is currently putting together a series of maps for the Temagami area. Perhaps they will be able to provide a conclusive answer to this mystery.
In the meantime, I would consider visiting the north knob of Ishpatina sometime.