The Great Exhibition was opened on 1 May 1851 by Queen Victoria. It was the first of the World's Fair exhibitions of culture and industry. There were some 100,000 objects, displayed along more than ten miles, by over 15,000 contributors. Britain occupied half the display space inside with exhibits from the home country and the Empire. France was the largest foreign contributor. The exhibits were grouped into four main categories—Raw Materials, Machinery, Manufacturers and Fine Arts. The exhibits ranged from the Koh-i-Noor diamond, Sevres porcelain and music organs to a massive hydraulic press and a fire-engine. There was also a 27-foot tall Crystal Fountain.