Anonymous About 3200-3500 B.C. [84 kb]

Most scientists believe that the wheel was invented 5000 years ago. The oldest wheel known was discovered in Mesopotamia and is believed to date back 55 centuries. A Sumerian (Erech) pictograph, dated about 3500 BC, shows a sledge equipped with wheels. The idea of wheeled transportation may have come from the use of logs for rollers, but the oldest known wheels were wooden disks consisting of three carved planks clamped together by transverse struts. Spoked wheels appeared about 2000 BC, when they were in use on chariots in Asia Minor. Later developments included iron hubs (centerpieces) turning on greased axles, and the introduction of a tire in the form of an iron ring that was expanded by heat and dropped over the rim and that on cooling shrank and drew the members tightly together. We don't know whom to thank for the wheel, but think of what the world would be like without it. No bicycles. No roller-blades. No cars...buses or trains. Days of walking to get from one place to another. No spinning wheel for Sleeping Beauty, no gears, no shopping carts...