Named for Queen Victoria's otherwise anonymous fourth daughter (who also lent her name to the province), Lake Louise is a place that requires multiple viewings. Aside from the standard picture-postcard shot (blue sky, even bluer lake), try visiting at six in the morning, at dusk in August, in the October rain or after a heavy winter storm.
You can rent a canoe from the Lake Louise Boathouse and go for a paddle around the lake. Don't fall overboard – the water is freezing.
