Peyto Lake seen from Bow Summit
The lake itself is located near the Icefields Parkway. In summer, large amounts of glacial flour and glacial milk flow into the lake from nearby glaciers; these suspended rock particles give the lake its bright turquoise color.
It was named after Bill Peyto, a former park ranger, trapper and mountain guide.

The "wild" Bill Peyto was a pioneer, mountain guide and early park ranger of Banff National Park. Peyto lived in England before emigrating to Canada in February 1887 and settling in the Canadian Rockies, where he worked as a railroad laborer. In the mid-1890s, Peyto built a log cabin near the Bow River where he stored equipment for hunting and trapping. Peyto worked as a park ranger in Banff National Park from 1913 until his retirement in 1936.

Peyto was best known for his services as a mountain guide and was selected to lead many prominent British, Swiss, and American climbers on numerous expeditions in the Canadian Rockies.

Bill Peyto was one of the leading figures in the Brotherhood of Mountain Guides and Packers that flourished at the turn of the century, and his knowledge of the mountains that surround us was surpassed by few. Bill was described as utterly fearless and was always willing to take any risk to protect those entrusted to his care. The Peyto Glacier on the Continental Divide and Lake Peyto are named in his honor.