I believe it was early one morning, in 2005 on a weekend all day exploration that we came across this site on the way East to explore some other sites in Eastern Ontario. It would have been about 6 am or so when we came across this gloomy looking site near Highway 7 on the way to Peterborough, Ontario. Initially we thought it might have had something to do with aircraft navigation or some sort of Pinetree Line early warning system, but it turned out to be nothing more than a Bell Relay site. A local ham radio tower now occupies the site and is the sole user of the tower.
These Microwave Relay sites used to be the primary means of long distance calling before Optical Carrier lines (fiber-optics) took over. Microwave stations were point to point, and line of sight, using radio waves at a very high frequency to communicate. These were the backbone of the trunked communications networks in North America and Europe from the 50's onward into the 80's. Due to the line of sight nature, relay stations such as this had to be located along the path of a signal between the various CO's. In this case it was between Toronto and Peterborough, eventually continuing on to Ottawa. There were 9 such relay sites along the route from Toronto to Ottawa, to give you an example of the infrastructure needed to maintain this system. Below is a map of the area. I believe this site was either Bethany or Hastings.
The Optical Carrier lines which now replace these microwave stations mostly travel long distances along side railways. In Canada, CN Rail was given an incentive to lay several fiber optic cables along each mainline for Bell Telephone use. In return CN was able to use several strands for their own purposes.