Clocaenog Forest is in West Denbighshire/Conwy, Wales. It is 40 square miles in extent, mostly coniferous softwoods under the control of the Forestry Commission. It is a highland region (mostly above 350 metres). It experienced a severe winter in 1946/47 with over 150 centimeters of lying snow on flat ground recorded at Clawddnewydd (a nearby village), and there was another hard winter in 1962/63. It is also the last mainland stronghold of red squirrels in Wales.

It was planted in 1905 on what was mostly moorland, and also took up many acres of small farmers land.