Winters in Canadian Rocky Mountains are long and cold.  But outdoor activities don't stop;  they just shift focus.  Many world class ski resorts are here, and for backcountry enthusiast ski touring and snowshoeing opportunities are limitless.  In second half of February I did an awesome snowshoe ascent of Dolomite Shoulder along the Icefields Parkway, some 20 min north of Lake Louise;  well off the beaten track, with huge scenic rewards.  There are inherent risks when venturing into back-country any time of the year, but specially in winter:  avalanche risk, slides, windchill etc.  Such trips require experience and higher dose of self-reliance, at least for people like me that generally hike alone.  But the freedom, far away from "civilization", and even sense of accomplishment make it all worth while!

You can read more about this trip and see many more winter wonderland photos here