The wheel symbolizes the first invention to the extent that the unnecessary rediscovery of any simple idea prompts the cliché “reinventing the wheel.” But the wheel is far from the earliest invention. In the history of humanity, the wheel is recent. It is not known for sure what the first invention was, but our ancestors were making a vast array of tools for a couple of million years before anyone got around to the wheel. The wheel was invented before it was used for transportation. The first wheels were potter’s wheels. Before the potter’s wheel, nature was essentially without wheels of any kind, as only a few microscopic animals, certainly unknown to early humans, possess anything like wheels for any purpose, especially not for transportation.

As with most inventions, the wheel not only had predecessors, it also required a number of related inventions before it could be useful. This concept is exploited for humor in Johnny Hart’s comic strip B.C. An early inventor appears with his wheel, although he has failed to invent the cart, to build the road, or to domesticate the animal that would make his wheel of any use. Instead, he travels on it by standing on projecting axles and simply rolls along, downhill one presumes.

Before there were wheels, people dragged things across the ground. To help them in this task they first devised various forms of yokes, so that two or more persons or animals could work together to drag the same heavy load. A later invention, sleds of one form or another, could do a better job of dragging something that was too heavy to lift. One virtue of a sled is that it has nothing to catch on uneven surfaces as it is dragged. Where there was ice and snow, sleds –– even in their highly individual form of skis (one sled for each foot) –– are especially effective. Mesolithic rock carvings from Scandinavia show people skiing. A sled –– also called a sledge –– is clearly depicted in a pictograph dating from about 3500 BCE in Uruk in Mesopotamia. Just as clearly, one of the earliest wheeled vehicles, looking like a sled on wheels, is in the same drawing. Similarly, in one early cuneiform script the symbol for sledge existed first, a virtual pictogram of a sled with turned up runners. At a later date, the same symbol was used with wheels attached to mean cart. Thus, the cart was an easy step from the sled.

It is widely assumed that an immediate predecessor of the wheel consisted of logs used as rollers for moving such heavy objects as the stones used in building the pyramids. There is no evidence for this. Early wheels are from Mesopotamia, where there were few logs in existence. The Mesopotamian wheels featured three planks cut and joined to make a wheel. Because of the grain in wood, wheels made by slicing a round section from a log tend to fall apart rapidly. Wheels can simply be attached to the sides of a cart with short axles on which the wheels turn independently, but early wheels were fixed to long axles that rotated as the cart moved.

The first use of the wheel was probably not utilitarian at all but ceremonial: Carts were used to transport effigies of deities and important people. Since important dead people were carried in the first such carts, it might be said that the hearse was invented before other forms of cart. The use of the cart for the transport of goods appeared about 1000 years after its invention.

Wheeled vehicles were used in war from early on. In Mesopotamia, four-wheeled wagons served as platforms for javelin throwers; two-wheeled war chariots also appeared first in Mesopotamia. Chariots were easily maneuverable because of the use of the much lighter spoked wheels, which were first known in Egypt about 2000 BCE.

The wheel spread from Mesopotamia quickly into Northwest Europe. Wheels also came into use around that time in India and China. In Egypt, the wheel became known about 2500 BCE. However, the use of the wheel remained unknown in large parts of the world including Southeast Asia, Africa south of the Sahara, and Australia and Polynesia, until much more recent times. Carts for transport disappeared subsequently in many areas around the beginning of the common era, including the Far and Middle East, because of the introduction of the camel for transport. The camel was far better suited for travel through desert areas than oxen drawing carts; oxen are slow and require abundant water.

Sleds and their close relatives continued in use in the Americas until after the arrival of the Europeans, although wheeled toys are known from pre-Columbian Mexico as early as 300 CE. In the mountains of Mexico and the Andes, goods were transported by carriers or pack llamas traveling along trails unusable by wheeled vehicles.

Historians are not certain when wheels became part of mechanical devices; however, such use is older than in transport, since the potter’s wheel preceded the appearance of wheeled vehicles by a thousand years. Eventually, of course, the wheel found many uses in cogs, gears, pulleys, and all sort of machines.