The River Llugwy (Afon Llugwy in Welsh) is a tributary of the River Conwy which has its source at Ffynnon Llugwy, a lake in the Carneddau range of mountains in Snowdonia.
The average annual rainfall in the catchment of the Llugwy is the highest recorded in England and Wales. The Llugwy follows the A5 until its confluence with the Conwy in Betws-y-Coed. On its route it falls over the Swallow Falls, and is then crossed by the Miner's Bridge, a curious wooden bridge set at a steep incline over the river. Both are very popular tourist attractions.