We awoke on day 2 to find the entire valley in front of us covered in thick smoke. The wind had shifted and all the output from two major fires burning south of us was emptying directly into the valley that held our route. Thick smoke obscured Summit Chief Mountain, and made it difficult at time to see much further than a couple hundred feet. Dismayed, but determined, we decided it was still worth pressing on.
As we started the smoke cleared some which made all the route finding we had to do far easier. Once you leave Tank Lakes, head southwest (follow the trail). For the first 1/4 mile or so there is a small trail that disappears and reappears over and over again.
Just do your best to follow and when it starts to look like you are walking toward some cliffs pull out your map and start route finding.
The route that we took, there are several I have heard of, leads downhill into a basin. From here The general idea that we used was first to follow cairns (if they looked to be leading in the right direction), and to pull out our compass every now and then. Once down into the first basin we made a giant rookie mistake. We chose to stay low and on the east side of Iron Cap Mountain. From here we attempted to work our way north and then around the north side of Iron Cap, without paying attention to the steep grade that the mountain turns into. We ended up climbing a (half) dry waterfall to get high enough up on Iron Cap to get around the north side.
Brandon Climbing Up The (Mostly) Dry Waterfall. If You Follow Our Route, Stay High On The East Side Of Iron Cap
Iron Cap Lake
As you can see from the photo above, this probably wasn't the best route to take. When we reached about half way up the east side of Iron Cap Mountain I spotted a cairn and we were back in business. Not that the route gets any easier, since it doesn't, but from here there were more cairns at least.
Once we were back on route we again seemed to run into a cliff-band that was nearly uncross-able without rope which we did not bring. We were able to discover that there is a small ledge and a couple of gulleys that allow safe passage around Iron Cap Mountain. This portion was quite nerve wracking and may be exceptionally difficult to get through for those with a fear of heights.
Either way we were able to make our way around and into the basin that holds Iron Cap Lake. From here the trail does actually start to ease up a little bit.
On the PDF map of our route it will be much easier to see, but, from Iron Cap lake, you want to head around the moraine that is on the right in the picture above, then follow it out and around the end of the ridge. Once you have gotten outside of the ridge line you'll want to follow the cairns (if available) and just head in the general direction of Chetwoot lake you can see on the map. This will eventually lead you to the outlet stream for Chetwoot where you will find a fisherman's trail. This trail will lead to Big Heart lake.
I would sincerely implore anyone who is doing this route to take three days and stop at Big Heart lake (or earlier) for one last camp. We pressed on exhausted and worn thin by the ordeals of traveling through the back country. We ended up back at or cars around 10 pm. Much of the way out was in the dark with little water, an experience I am not ready to soon repeat.