Perhaps the greatest contributions of the Sumerians was the invention of the wheel; it allowed merchants and others to transport items over much further distances and soon was adapted to a plethora of other uses. Among their other accomplishments was the creation of bronze by combining copper and tin, and later the ability to forge tools and weapons from iron. Another important contribution was the development of a system of writing, in the case of Sumeria this was cuneiform. The development of writing led to the expansion of knowledge and scholarship, and allowed for its preservation for future generations. Finally, the Sumerian numerical system of base 60 is the foundation of our modern system of measurement of degrees, distances, even time. The Sumerians were the first to develop a twelve month calendar, a sixty minute hour, and a sixty second minute.
^many of these are characteristics of Mesopotamia which can be deemed the same has Sumer, but is slightly different