In 1901, the Surveyor-General of Canada, Dr. Edouard Deville, assigned Wheeler the task of surveying the Rogers Pass area of the Selkirk Range in British Columbia. On the train to Rogers Pass, Wheeler met Edward Whymper, who had made the first ascent of the Matterhorn in 1865 and who was in Canada as a guest of the Canadian Pacific Railway. At Rogers Pass, Wheeler met a group of professional Swiss mountain guides in the employ of the railway, and it was with six of them that he made his first ascent of a major peak. He continued to climb mountains in the area, and in 1902 took his son Oliver on a first ascent of a previously unnamed peak, which he named Mount Oliver after his son. Wheeler also made a first ascent of a major peak, which he named Mount Wheeler after himself. In 1903, Wheeler was assigned the survey of the railway belt through the Canadian Rockies east of Rogers Pass. During the following two years, he met numerous American and British climbers who were making first ascents among the vast ranges of unclimbed peaks in the Canadian west.