Not really a route so much as an alternative to skiing directly alongside the tracks. The NW snowfields are generally stripped down to talus by the wind, but when there is a heavy layer of Rime Ice or snow that hasn’t been transported by the wind, these snowfields can be a very fun, surprisingly shark free, low angle descent. Simply traverse left from the Cog, a short downhill through a rocky slope gives way to wide open, low angle turns. Traverse right before you get lulled into the North Branch of Ammo. In good conditions you can ski the ridge left of Jacob’s Ladder to a flat bench, where you can pass under the tracks to regain the cog. Be aware of annoying spruce traps as you re-enter treeline. These can be a pain and really hang you up in lean conditions with unconsolidated snow.