The The Standard of Ur comes from the ancient city of Ur (modern Iraq south of Baghdad). It dates to the Early Dynastic period and is 4,600 years old. The standard was probably constructed in the form of a hollow wooden box with scenes of war and peace represented on each side through elaborately inlaid mosaics. Although interpreted as a standard by its discoverer, its original purpose remains enigmatic. It was found in a royal tomb in Ur in the 1920s next to the skeleton of a ritually sacrificed man who may have been its bearer. The chariots are depicted in detail; each has solid wheels (spoked wheels were not invented until about 1800 BC) and carries spare spears in a container at the front. The arrangement of the horses' reins are also shown in detail, illustrating how the Sumerians harnessed them without using bits, which were only introduced a millennium later.