The wheel was supported by two 140-foot (43-meter) steel towers. The 45-foot (14-meter) axle was the largest single piece of forged steel at the time in the world. The wheel itself had a diameter of 250 feet (72 meters), a circumference of 825 feet (251 meters), and a maximum height of 264 feet (80 meters). Between the two rims of the wheel, Ferris hung 36 wooden carriages, like railroad cars, that could hold 60 people each. Every car hung from its own axle. This meant that the cars would swing slightly back and forth as the wheel slowly rotated, but they, and the people inside them, always stayed upright.