Blaenau Ffestiniog is a historic mining town in Gwynedd, Wales. It has a population of 4,875 according to the 2011 census, including the attached village of Llan Ffestiniog, which makes it the third largest town in Gwynedd unitary authority, behind Bangor and Caernarfon. Although the population reached 12,000 at the peak of the slate industry, the population fell due to a decrease in the demand for slate. Blaenau Ffestiniog at one time was the second largest town in North Wales, behind Wrexham. Today, the town relies heavily on tourists, who come to see the many attractions within and around the town such as the Ffestiniog Railway and the Llechwedd Slate Caverns.