Have driven to and from the West Kootenays for years ( Kimberly in the East Kootenays) as my oldest daughter lives between Calgary and Banff.
Hands down the best route is Q-2 to the NW Stoney Trail ring road to ( 201) to Hwy 1 west to Banff.
Then take Castle Jct to Hwy 93 to Radium Hot Springs, then follow Hwy 93/95 south to Wasa lake and then Hwy 95-A into Kimberly.
I had two daughter that lived in Calgary at one time, so I have driven both routes many times over the years.
I had one daughter in the NW and one in the SW, and winter driving through the Crows nest pass is far more hazardous than the route I just gave you above.
You have one hill climbing out of Castle Jct and then one hill up to the summit above Radium and then the hill down into Radium, that's it. Use your transmission and 4 way flashes when going down the hill into Radium. I pulled my 35 ft 5 wheel up and down the routs many times... just take it easy you will be fine.
The roads are kept in great shape all the time. However bad weather can make any road sketchy, and can happen any time. I will drive through the Park any day, in stead of Crows Nest Pass. .
Soup.
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