Located in the former Ratho Quarry, on the north bank of the Union Canal, just to the west of the village of Ratho, the Edinburgh International Climbing Arena (formerly Ratho Adventure Centre) is home of the National Rock Climbing Centre and the world's largest indoor climbing arena. The quarry, which finished operations in 1926, provides natural rock faces which have been used by climbing enthusiasts for many years. These have been augmented by artificial walls, which can have their hand-holds adjusted to give new and challenging climbing routes. A remarkable piece of architecture, the centre opened in 2003 and represents a £24 million development, built with the support of Sportscotland and the Mountaineering Council for Scotland. In addition to climbing, the centre includes a health club together with the National Academy of the Scottish Judo Federation and facilities for scuba-diving. It also houses 90-person accommodation, an auditorium, restaurant, bar, conference and concert facilities.
Following financial difficulties, the centre was taken over by the City of Edinburgh Council in 2005.