... This is more of a
vacation that a form of transportation. Since you are looking for cheapest, I would rule this out. The other passenger train goes through Jasper, viarail, this should be cheaper. Most people just rent a car or you could fly to Calgary and go to banff ...
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... time (daylight,) a one way
rental car with a departure home from Calgary (just add a third to the advertised
rental rate for taxes etc.), or the Rocky Mountaineer, which overnights in Kamloops, would be your answer.
If you decide to fly, remember to add ~50% to the advertised airfare ...
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