Harrington Lake Diefenbaker suggested that he needed a quiet place to go fishing, not too far from Ottawa. Later that year, Harrington Lake was chosen as the site for an official country residence and the buildings were formally designated as a secure residence for Canada’s prime ministers. During the first prime ministership of Pierre Trudeau, his then-wife, Margaret, added a vegetable garden; according to Kim Campbell's autobiography "Time and Chance", the garden still provided the house with fresh produce at the time of that writing. Campbell was the only Prime Minister to have spent her entire term in office residing at Harrington
Harrington Lake for several decades. Since the land was not suitable for farming, the lumber industry replaced it as the primary economic activity. In the early 20th century, two Americans, W. A. Drum and W. L. Donnelly, built a sawmill at Harrington Lake to serve the lumber industry. In the 1920s, Lieutenant Colonel Cameron Macpherson Edwards, a member of a prominent lumbering family in Ottawa, inherited part of the property from his uncle, Senator William Cameron Edwards (who had owned 24 Sussex Drive). He recognized the value of the land for recreation, as well as for lumber. He purchased more land around