Like others have posted, getting reservations is a must the first day they allow to do so - especially if you want electric hookups.
It is highly recommended for reservations upon any campsite if visiting during June thru Labour Day Weekend.
Unfortunately I am still a working stiff and my boss only allows me September off for vacation time, and that's still like pulling teeth or takes an act of congress to approve it, while I get the "take time off during the winter" speech, as my line of work does not allow summertime off.
So, upon my experiences of visiting the Canadian Rockies in the Banff, Jasper, Yoho, and Kootenay National Parks - I was only able to tour the region during the month of September in 2011, 2012, and 2013 - and STILL haven't been able to see everything in the area....
I could only stay 4 to 5 days in the area before heading back home so I could still keep a job - taking my time commuting in my old 1970 rig via Alaska or Cassiar Hwy. it would take me 9 to 10 days time to arrive, so that would be about burning three weeks of vacation time just on commuting alone upon a round trip.
Had to cut my vacation short and head back in 2014 as I gotten a high fever and tonsilitis, or else I would have had all of my four different national park entry passes which I planned on getting :
2011 - east entry - Banff - (check)
2012 - south entry - Kootenay - (check)
2013 - north (w) - Jasper - (check)
2014 - had planned west entry to Yoho to obtain the four cycle of park passes, so I have yet to acquire that still.
During September, just the few main featured campgrounds do remain open as Parks Canada shuts down the others...
I have never had to make any reservations for an available campground site in any of my visits during September, however other than Lake Louise - Tunnel Mountain II (all electric sites) were always FULL and Whistlers (electric sites) were always FULL also....
I stayed at Lake Louise campground in 2011 and 2012 :
(availability was plentiful)
All sites are electric there for RV spots (189 sites), with easy and roomy two way access sites (drive in and out the other side) for even a motorcoach size rig in the middle portion of the RV campground, very maneuverable there...
The only downfall for some people at Lake Louise : is the trains run fast thru the campground and are real loud in all hours of the day and night, however they never bothered me as I wear earplugs when sleeping in the RV and I always wear hearing protection when walking around in public anyway to filter out the annoying noises and screaming kids and such.
I was possibly planning to stay at Redstreak at Kootenay NP in 2012, however that campground was FULL.
I stayed at Whistlers campground in 2011 and 2012 as well :
(I lucked out as in 2011 there were only 5 sites left, and only 2 sites left in 2012) - like I mentioned before - no electric sites were available as they were all taken......sites assigned to me were small.
If one thinks the trains are real bad at Lake Louise campground, try dealing with constant continuous loud mating calls of elk during the night at Whistlers in September - I say pick your poison in comparison.
Wapati campground closes during the month of September at Jasper Nat'l Park as they upgrade it for winter season.
I stayed at Tunnel Mountain I campground (no electric sites there) in 2012 and 2013 - sites are small that they assigned me just like Whistlers, however I was commuting in a cabover camper so it was fine for me.
I stayed overnight in the parking lot at Icefields Visitor Center (Jasper NP) in 2013 and stayed at Two Jack Main campground in 2013 as well....
Two Jack Lakeside campground sites were all full, as I overnighted in Two Jack Main campground on the final day they scheduled to close for the season - was planning on possibly taking the Lake Minnewanka boat tour however I didn't think the weather was going to hold up long enough during the day as I passed it up with threatening rainfall, and it did rain hard by mid day.
As for all that are reading this post, this gives one the idea that every one of those consecutive years that I visited the four National Parks, I visited different sites and other areas that I previously have not explored.
Will post more pictures time permitting, however I will close a few for now, pertaining to the trams and ski lifts :
September 2011 - Lake Louise Ski Lift and Mountain Resort - Banff NP :
September 2011 - Whistlers Mountain - upper terminal - Jasper NP
September 2012 - Sulphur Mountain - overlooking lower terminal - Banff NP
Sulphur Mountain - upper terminal - Banff NP
As noted, places like Waterton NP, the Kananaskis, Mt. Robson, etc. and such along the Canadian Rockies in those areas are a must see also if one has the time to visit.
1975 Ford F250 2WD Ranger XLT (Owned June 2013)
460 V8- C6 Trans- 3.73:1 (196K Total Mi)
2000 Fleetwood Angler 8ft Cabover
Air Lift 1000 (Front)
Hellwig 3500 lb Helper Springs (rear)
Hellwig Front and Rear Sway Bars
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