Here you will find the remains of the Mill Pond and the Sawmill at Limehouse. The trail south from here follows the bed of the former Toronto Interurban Rail Line.
You can access the ruins from the Bruce Trail access points (at Limehouse Conservation Area or Limehouse Memorial Hall at 22nd SR and Fifth Line). The Kilns and the Ruins are crumbling, so it is vital that you remain on the trail.
Lime Kiln Cross Section - from limehousekilns.ca
The Lime Kilns seen here were used extensively in the 1800's to produce Lime from the combustion of limestone (lots of that to be found around here). The Mill and Kilns were shut down in the early 1900's as modern equipment replaced this labour intensive method.
Wood (presumably from the sawmill) was piled at the base of a kiln and ignited. Limestone was piled in from the top, and lime slate was removed from the bottom. The temperatures inside a Lime Kiln would often reach 1900 degrees celsius. These kilns could process 75 tonnes of limestone a day.
For a detailed description of the Lime Kilns and how they were used, visit the Limehouse Kiln Society web site - http://www.limehousekilns.ca/history.htm
There is another excellent article on Limehouse's History found here - http://www.limehousekilns.ca/images/Out%20of%20the%20Limelight.pdf