When was the wheel invented?

It is not known exactly when the wheel was invented. The Sumerians used wheels about 5000 years ago in Mesopotamia. They first used it as a potter's wheel, and a few centuries later as a wheel on carts. In their excavations in Northern and Western Europe, archeologists have found remains of discs from the Stone Age. The wheels of the Sumerians were wooden discs, which were fixed on an axis with spikes. The first wheels with spokes also originated in Mesopotamia. Around 2000 BC the Sumerians built these lighter wheels for their war chariots, as did the Egyptians around 1600 BC.