The Mid Canada Line Test Fence Station 012 in Ottawa is a historic site from the Cold War era. It does not have a plaque or a marker. The information I have found about it is incomplete. The ruins of this site occupy a location east of Old Prescott Road opposite its junction with Thunderbird Drive.
The Mid Canada Line consisted of a series of stations along Canada's 55th parallel, approximately 54º to 56º northern latitude. The stations were used during the Cold War from the late 1950s to the mid 1960s for the purpose of providing early warning of a Soviet bomber attack on North America. The system used a series of towers using what is called double doppler radar transmitting and receiving simultaneously between each pair. Any aircraft flying into the system from an altitude between a hundred feet and sixty-five thousand feet would be detected without determining the size and exact location of the aircraft. Essentially the system operated like a trip wire or fence, hence the Mid Canada Line was also known as the McGill Fence.
Before the operational components of the Mid Canada Line were built a test system or Test Fence was installed between Ottawa and Mattawa along the Ottawa River, at a latitude of about 45º north. This system went by the code name 'Spider Web.' The site shown here was site 012 Ottawa. The site is in South Gloucester, which was south of and outside Ottawa's borders when it was installed in 1953, as part of a contract involving the Eaton Electronics Research Laboratories of McGill University.
Rennie Whitehead, project leader for the test fence, working for the University, identified the site locations: Ottawa, Arnprior, Haley Station, Meath (near Pembroke), Deep River, Bisset Creek and Mattawa. Except for the Ottawa site shown here the exact locations of the other six sites are not known at this time. Those locations may be some distance from the communities named, just as the Ottawa site was some distance from Ottawa when it was put in place.
The Mid Canada Line was the second of three lines used for the detection of Soviet bombers approaching North America. The first one, named the Pinetree line, began with planning as early as 1946 and began becoming operational in 1951. It consisted of a series of radar stations in the United States and Canada at about the 50th parallel. Many of the stations remained operational into the 1980s. The third, and probably best known line, the Distant Early Warning Line or DEW Line, became active in 1957 and remained so until 1993. It comprised a system of radar stations in the far northern Arctic region of Canada, with additional stations along the North Coast and Aleutian Islands of Alaska. Of the three lines the northernmost DEW Line provided the most capable early detection.
The Spider Web trials were followed in 1954 by intensive tests on a single thirty miles (48 km) wide link, built in the Eastern Townships of Quebec. Although I did not find any mention of when the Mid Canada Line Test Fence was shut down I am assuming the sites were closed and the Ottawa site was abandoned in 1954.
Although the site is accessible I recommend not visiting it. It is completely overgrown and the terrain surrounding it is uneven with plants that make it difficult to see the ground, which in early spring or after wet weather is highly likely to be boggy. Those who insist on visiting would do well to wear protective gear.