Grassi Lakes

Glass-green lakes up a trail a coal miner built himself, with thousand-year-old paintings past them

The Upper and Lower Grassi Lakes are two small, emerald-coloured pools at about 1,525 metres in the southern Canadian Rockies, looking down over the town of Canmore, Alberta. They are fed by water from the Spray Lakes Reservoir on the Spray River and lie in Canmore Nordic Centre Provincial Park, part of the Kananaskis Country system, at the foot of grey cliffs about 75 metres high.

They carry the name of the man who built the trail to them. Andrea Lorenzo Grassi was born in Falmenta in Piedmont on 20 December 1890 and came to Canada in 1912 as Lawrence Grassi. He worked for the Canadian Pacific Railway for several years, then went down the Canmore coal mines in 1916 and stayed a miner until he retired. In his own time he climbed, guided and built trails, around Canmore and at Lake O'Hara in Yoho National Park, and became a respected climbing guide. Plaques along his trails honour the work, and his name is on Mount Lawrence Grassi, Grassi Knob, these lakes and a middle school. He died in Canmore on 5 February 1980.

The cliffs behind the lakes are older than the mountains' human story by a very long way. They belong to the Cairn Formation, a fossil reef built during the Late Devonian by stromatoporoids, long-extinct sponges of bulbous shape. The pockets the sponges left behind make natural hand- and footholds, and the cliff is a favourite with rock climbers.

Past the lakes, near the top of the canyon beyond them, are rock paintings more than 1,000 years old, believed to be the work of Kutenai ancestors. Under a rocky overhang, signposted from the trail, they include a figure known as the Medicine Man, a human shape holding what looks like a large hoop, and Travel Alberta counts them in better condition than the pictographs across the Bow Valley at Grotto Canyon. Rat's Nest Cave nearby, visited only on guided tours, holds a similar Medicine Man.

The lakes are a favourite of hikers and climbers alike. Take in the paintings with eyes and camera only, and keep hands off the rock so they last another thousand years.