William Clark & Sons
William Clark & Sons is the oldest linen mill in Northern Ireland and the textile company founded in Maghera, County Londonderry in 1736.
The main product is a fine linen canvas for the tailoring industry, used is a unique process of beetling - pounding of the fabric to flatten it.
In February 2017 a fire destroyed one of the factory buildings, but the production was intact.
The Mills power source was from the Knockoneil River which is an artery of the Clady River.