Jasper's little heritage train station sees a veritable onslaught of trains, at least by Canadian standards, in the summer high season. Seeing the magnificence of the Rockies by train is certainly an attractive option and considering that the whole area was originally opened to visitors thanks to the development of the railways, and that tourism goes back hundred and fifty years around here, a time honoured one.
The main train service that passes through Jasper is the flagship service of the ViaRail Canada, the passenger operation of Canada National – or rather, what's left of it – The Canadian. This long-distance train runs three times a week between Toronto and Vancouver all year round. The train going west leaves Jasper at 1.30pm, to arrive at Valemount at 4.07 (Pacific Time), Blue River 6.27pm, Clearwater 8.44pm and Kamloops North at 11.09pm. This is a great ride through a very picturesque part of the Rockies – taking in Mount Robson – and one of the best ways to taste the railways-in-the-Rockies experience. The other way round might be even better, as the train leaves Kamloops at 6.35 in the morning, so the whole ride is pretty much in the daylight – unless you are travelling in the depths of the winter – and in fact you can go most of the way to Edmonton in the daylight, if you fancy seeing some of the prairies too.
In addition to The Canadian, Jasper is also a stop on some of the Rocky Mountaineer excursion routes, namely the Whistler – Quesnel – Jasper trip and the Vancouver – Kamloops – Jasper trip. These are "attraction" trains, with no pretence to be a means of travel for any other purpose than pure tourism, and have to be seen as train tours. The trains stop overnight, and hotel accommodation is included. This has a major advantage (no loss of sightseeing opportunities), but makes the whole package massively more expensive than just taking a Via Rail train. Frankly, if I considered taking one of the Rocky Mountaineer packages, I would go for one that incorporates Banff and Calgary, as there is no Via Rail trains on that route at all. Of two that call at Jasper, the Whistler one is both more attractive and cheaper, starting at around 800 CAD for two days on the train and one night accommodation. Comparable Via Rail ticket costs around 150 CAD – this would leave you with more than enough for any hotel stays. Even in a sleeper class, which also includes meals, Via Rail is less then 500 CAD.
A less known but potentially fascinating alternative or extension is a Via Rail train to Prince George and Prince Rupert. This also runs three times a week, but unlike The Canadian, doesn't offer a sleeper accommodation, instead having an overnight layover in Prince George. This route takes you at first through some very attractive stretches of the Rockies, including the Yellowhead Pass and Mount Robson, to then continue through pretty wild country towards the north of BC. In the summer, it's possible to catch a daytime BC Ferries boat in Prince Rupert and come back down the glorious Inside Passage to Port Hardy at the northern top of Vancouver island. Prices on this route start at around 120 CAD, which makes it excellent value (but you need to include a accommodation in Prince George). It is also possible to take a shorter trip from Jasper and stop and turn round - provided you have some form of transport ready, or accommodation to wait for the return train next day – at one of many stops between Jasper and Prince George. Most of them are request stops and need advance notification.