Cragside is a country house in the civil parish of Cartington, near Rothbury in Northumberland, England. It was the first house in the world to be lit using hydroelectric power. Built into a rocky hillside above a forest garden of just under 1,000 acres, it was the country home of armaments manufacturer, Lord Armstrong, and has been in the care of the National Trust since 1977. The property was eventually opened to the public in 1979. In 2007, Cragside reopened after undergoing "total refurbishment."