The station was on the 1 ft 11+3⁄4 in (603 mm)[6] narrow gauge Festiniog and Blaenau Railway (F&BR); it opened with the line on 30 May 1868.

[8][9] In common with Festiniog and Tyddyngwyn stations, the only published photographs were taken from a distance, lending the buildings the appearance of corrugated iron.

Loaded wagons would descend the inclines from Manod and Craig Ddu slate quarries to Tany-y-Manod then be hauled northwards to the FR, who forwarded them to customers or to ships at Porthmadog Harbour.

Narrow gauge trains continued to operate during the conversion, using a third rail and a diversion around the wooden viaduct north of Tan-y-Manod, which was demolished and replaced by a stone version.

[16] The Bala and Festiniog Railway, then later the Great Western developed Tan-y-Manod's facilities and priorities, they in their place they installed: Each transshipment siding (sometimes referred to as a transfer dock or a wharf or a loading bank) had either one or a pair of narrow gauge lines raised on a platform meeting a standard gauge line end-to-end.

[26] The GWR, like the LNWR and the FR, provided the quarry owners with free use of narrow gauge wagons in an attempt to promote the use of their own route.

[22] Slate traffic using the transporter wagons continued until Craig Ddu quarry closed in 1945, after which the transfer sidings lay disused.

The engine shed - a sub-shed of Croes Newydd - closed as long ago as 1906, but it was clearly in use for some purpose in 1936.

In Spring 2016 the mothballed single track line still ran past the site to the former nuclear flask loading point.

[35] On 21 September at least one regional newspaper reported that "Volunteers are set to start work this weekend on clearing vegetation from the trackbed between Blaenau Ffestiniog and Trawsfynydd."