The distillery was opened in 1894. It is situated on the River Isla. Originally its product was used in Haig's blends but after a period of inactivity from 1983 it was re-opened and now produces the single malt known as An Cnoc.
The name 'Knock' is from the Gaelic 'cnoc' (pronounced 'krochg') which means a small hill or knoll, and '-dhu' is from 'dubh' (pronounced 'doo') meaning black or dark, in both the literal and the figurative sense. So 'Knockdhu' means 'Black Rock'.