aspen, which cover most of the area; and from the ancient Canadian Shield, with its five and a quarter million square kilometres of hard Precambrian bedrock, in whose thin soils the forests are rooted.

Once, a billion years ago, there may have been towering mountains here. No longer. The successive movements of glaciers – the last of their retreats dating back about 10,000 years – have left behind a mix of rolling uplands, wetlands rich in organic soil, and innumerable lakes, rivers, streams, and waterfalls. The Laurentian Highlands of Quebec typify the upland landscape of the Boreal Shield. Here can be found La Mauricie National Park, on a gently undulating plateau never more than 500 metres above sea level, and covered with dense forests and sparkling lakes and waterways.

At its eastern edge, the Boreal Shield offers spectacular upland landscapes in the Long Range Mountains of western Newfoundland, where Gros Morne National Park and its