Rockwood Woolen Mill

Sunday August 16, 2015

This hike explored the Rockwood grist mill, an abandoned house, the Harris & Co. Rockwood Woolen Mill and some glacial potholes.  I parked in the Lion’s Club park on Main Street near the river.  The first settler to the Rockwood area was John Harris.  He arrived in 1821 and built a small house and a saw mill.  Before long other mills were added including flour, stave, woolen and grist mills. Henry Strange was the Deputy Surveyor for the area and he opened a lime quarry which was used for the stone for the early mills.  The early name for the community was Strange’s Mills.

The grist mill was built on the side of the Eramosa River just east of main street.  It is made of local limestone and has been converted into a private residence.  The dam and mill pond remain intact but are now marked as private property.


Valley road leads into the park from the grist mill along the north side of the river and passes this small burned-out building.  A trail from here leads to The Devil’s Well.


John Harris built the first mills and this attracted further settlement and spurred the development of other mills and trades.  John and his wife Jane had six sons and adopted one daughter.  In 1867 his three oldest sons and one son-in-law joined together to start a woolen mill.  Under the name of Rockwood Woolen Mills they developed a reputation for quality products.  They advertised in the local papers for people to bring their fleece to the mill and trade it for their woven products.  They sold blankets and sheets as well as underwear and tweeds.  They also sold bleached cotton and yarn which they claimed to be “full weight and fair inspection”.  The picture below and the cover photo show the remaining ruins in the park.


The original woolen mill on this site was built from wood and burned down in 1880.  It was replaced in 1884 with a structure made from stone.  The tower has date stones to commemorate both the original construction in 1867 and the replacement building from 1884. The ruins of the mill have been stabilized by adding a layer of concrete along the upper edge of every wall.  This prevents the stone from being removed by weather and vandals and will help preserve the structure for future generations to marvel at.


The mill was powered by various means over it’s history.  Originally it was powered by water which was diverted from the river to power the turbines.  The arch below contains the raceway from the original turbine power system.  The original stone bridge structure across the raceway now supports a new pedestrian and vehicular bridge. Later the mill was converted to steam and finally to electrical power before it closed.


The mill reached it’s production peak during the First World War when it had to operate 24 hours per day to produce thousands of army blankets for the military.  Due to intense competition from other mills the business was closed in 1925.  The Harris family then converted the site into a park to showcase the local scenery and the glacial potholes.  The park was called Hi-Pot-Lo Park and was a popular destination for awhile. The park was acquired by the conservation authority in 1959 and converted into Rockwood Conservation Area.  The mill was destroyed by fire in 1965 and was reduced to the ruins that remain today.  This picture shows the Rockwood Woolen Mill as it appeared in 1890.  The company kept adding little out buildings which gave the complex it’s disorganized sprawl.


This Great Blue Heron was catching small fish along the side of the Eramosa River.  In the picture below it has a fish in sight which was in it’s belly seconds later.


There are over 200 glacial potholes in the Rockwood Conservation Area and another hundred scattered around the nearby area.  These potholes are believed to have formed during the melting phase of the most recent ice age.  Water containing fist sized rocks was caught in a swirling action that eroded these large circular cut-outs.  Along the pothole trail there are many complete and semi-circular potholes.


Painted turtles have four distinct subspecies that can be identified by the markings on their shells.  The eastern has aligned plates and southern has red markings on the top shell which allows us to determine that this is not one of either of those.  The midland has a grey patch on the bottom shell while the western has a red pattern below.  This specimen was a little too far out in the river for me to flip over to identify which one it was.


Some of the glacial potholes extend to 200 feet deep including one called the Devil’s Kettle.  This spot along the river shows where the rock has been worn away in a large circle above and below the present waterline.


As you drive down Guelph Line toward the 401 you cross the former right of way for the Guelph Suburban Railway (1917-1931) one of several Radial Railways stemming from Toronto in the early 1900’s. This spring we investigated a set of decaying, century old, bridge abutments from the railway over the Silverthorne grist mill tail race.  We then followed the right of way through Eldorado Park, it’s entertainment enterprise.  At Limehouse we saw the pilings for the trestle that used to cross the mill pond. This portion of the railway was purchased by the Halton County Radial Railway for the purpose of opening a railway museum.  This museum is a great place to visit as it houses many historic rail cars and features a ride on the rails.  At the roadside is this car from the London & Port Stanley railway.  It operated as an electric railway from 1913-1957.


A listing of the reader-selected top 15 hikes can be found here.

Google Maps Link: Rockwood Conservation Area

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5 thoughts on “Rockwood Woolen Mill

  1. Pingback: The Devil’s Well | Hiking the GTA

  2. Pingback: Old Mills of Southern Ontario | Hiking the GTA

  3. Pingback: Goldie Mill Guelph | Hiking the GTA

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