Sitting on the edge of the Niagara Gorge below the Canadian Horseshoe Falls is a long rectangular shaped building called thee Ontario Power Generating Station.
This plant built in 1905 (abandoned in 1999) at one time produced 25 cycle power. This plant received water to produce this power from three tunnels that took water from above the falls and transported it to the top of the generating plant. These tunnels connected to six penstocks six feet in diameter to the generators where power was produced. The water then flowed back into the Niagara River.
What I find interesting is these three tunnels can still be found below the Niagara Parkway and parking lots behind the Table Rock area. There are two steel tunnels and one wooden tunnel encased in cement held together by iron hoops.
When you travel the parkway between Table Rock House to the Illumination Tower (the old surge tank for the generating station) you are travelling over these abandoned tunnels.
Here’s a photograph taken from Ontario Hydro’s archives of the construction of the tunnels in the early 1900’s and a photo of the abandoned plant that I took from the U.S. side of the border.