Mountain climbing with all its thrills near Lake O'Hara in Yoho National Park, British Columbia. The film begins on a busy street in Toronto with cars and a Yonge Street streetcar contending with traffic, and pedestrians during rush hour. It then cuts to a mountain in the Rockies and Lake O'Hara and with four men with pack-sacks boarding train. They later climb past the Seven Sisters waterfalls. Coming to an alpine lake, they begin the ascent to the summit, using ropes and picks and traversing some tricky rock faces. Near the top they reach the 'Devil's Window' and, finally, the summit. The film was produced by the National Parks of Canada to promote tourism travel to the Canadian Rockies.