The Dinorwic Slate Quarry is a huge series of old Slate workings in North Wales near the village of Dinorwig. The Welsh National Slate Museum is situated at the bottom of the quarries at Llanberis which I will cover seperately. This was the second largest slate quarry in Wales after the nearby Penrhyn Quarry covering some 700 acres (2.8 km2) in two sections of 20 galleries plus secondary workings. Tramway systems connected the quarries using inclines to transport the slate. The quarry closed in July 1969 after a life of over 170 years as a result of industry decline and difficult slate removal due in part to unsystematic tipping of waste .By 1966 production had almost ceased. Some final working of rock falls was done to little affect and all work stopped in 1969. Most equipment was auctioned off including the famous quarry Hunslet loco’s but much was left resulting in huge amounts of standing industrial archaeology including tramways, inclines, drumhouses, compressor houses, some with substantial quantities of machinery still in them such as can be found on Australia level. Access is theoretically not allowed but seems tolerated, and the description and photos given here do NOT imply public access is permitted. A must to see before the weather takes its ultimate toll. The site is spreadout above and below the Padarn level to the SW, NE and SE of NGR SH592605, I would suggest further research on the web before attempting this site as it is vast!