The largest tire ever built was 80 feet tall and was used as a ferris wheel at the 1964 World's Fair in New York. The LEGO Group is the world's biggest tire manufacturer, producing over 300 million toy tires per year. Tires are made from a milky white rubber but carbon black is added, both to strengthen the rubber and turn it black. In the 1960s, Goodyear developed a translucent tire that could glow different colors by connecting light bulbs inside, though it was never intended for sale.