Slate industry in Wales
The slate industry in Wales is attested since the Roman period, when slate was used to roof the fort at Segontium, now Caernarfon. Slate is mainly used for roofing, but is also produced as thicker slab for a variety of uses including flooring, worktops and headstones. In 1898, a work force of 17,000 men produced half a million tons of...