Mountain Passes . Fog, low clouds, and snow squalls are the most serious, though when the wind gets up, at times the ride has to be experienced to be believed. I must admit I don't much like passes, and when I have the chance I fly above them, often IFR or above the clouds. Each time I have had to fly that route, the pass has been marginal to closed, and, being in an IFR airplane, I have climbed up to altitude, put on my oxygen mask, and shot the approach on the other side. I know too many pilots who have died in passes to feel fond of flying them when the weather gets low.
Rivers are one of the great navigation aids in the north.
Most villages and cabins are along them, and any major river will take you to civilization sooner or later. Large or small, rivers and creeks are your VFR highways through the bush. Large lakes . Large lakes can be spotted from quite a distance when at altitude, and make good checkpoints when navigating by dead reckoning or pilotage. The rest of it is just getting to know your basic area of operations well, as well as you know your cabin or airplane.