During the first World War, the Canadian Forestry Corps was involved in timber extraction between Rhyd Ddu and Beddgelert. Construction work on the section of the NWNGR south of Rhyd Ddu had resulted in some isolated sections of track that were extended temporarily for this work and worked using horses, gravity and winches. The Ordnance Survey of c.1916 shows continuous track from Rhyd Ddu to a short distance north of the later WHR Hafod Ruffydd halt.
Thomas Parry & Co, a timber merchant, reputedly obtained Muriel, a de Winton vertical boiler locomotive, from Glanrafon Slate Quarry around 1914 and used it to haul timber on the section of line up to his sawmill at Rhyd Ddu. The locomotive was sold or scrapped in about 1920.