Llechwedd (Welsh pronunciation: [ɬɛχˈwɛð]) is a visitor attraction near Blaenau Ffestiniog, Gwynedd, Wales. It details the history of slate quarrying in the town and specifically the Llechwedd quarry in which it is located. The main aspect of Llechwedd is its Llechwedd Deep Mine Tour which has the steepest narrow gauge railway in the UK and travels over 500 feet underground to the disused slate caverns, and the Quarry Explorer Tour which heads out to the furthest reaches of the Llechwedd site to explore the history of mining in the area.