The narrow-gauge Festiniog Railway in Wales is one of the country's leading heritage lines. Running from the slate-quarrying town of Blaenau Ffestiniog to the coast at Porthmadog, the line now carries countless thousands of visitors and tourists. Prior to passing into preservation in the 1950s, the Festiniog had an equally important role in the local economy as a means of shipping vast quantities of slate from the quarries in and around Blaenau Ffestiniog down to the harbour at Porthmadog where they could be shipped, either by standard-gauge railways or by ship to the rest of the country or overseas for the worldwide market. When the Festiniog Railway first opened in 1836 it was operated by gravity and horse power and steam locomotives were introduced during the 1860s. By the mid-20th century, however, changing economic circumstances forced the line towards closure and, had it not been for the preservationists, it would have become as much a part of history as the slate industry it was built to serve. This detailed analysis of the Festiniog will be of interest to modellers of the narrow gauge, those involved in the preservation and operation of the contemporary Festiniog Railway and all those fascinated by the local and industrial history of this part of Wales.