The entire trip took us about two hours in the winter. Definitely wear ice cleats or yaktrax/korkers at a minimum, we found slippery areas. The frozen falls are beautiful and numerous. You do not need a tour guide as the trail is well marked and safe. Remember that park facilities are closed in the winter, although there are pit latrines available if you need them. The drive from Banff took at about 45 minutes over well plowed (but not snow free) roads.
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