Moel Tryfan was a narrow gauge steam locomotive built for use on the North Wales Narrow Gauge Railways (NWNGRs) in 1875. The locomotive was an 0-6-4 T single Fairlie locomotive built by the Vulcan Foundry near Manchester. It spent its entire working life on the NWNGRs and its successors the Welsh Highland Railway (WHR) and the Ffestiniog Railway (FfR).