In the Paleolithic times human culture developed walking tracks called game trails from domesticated animals which carried goods for trade. Animals like horses, oxen and donkeys flattened these tracks to reflect a high density of traffic. The travios was invented and it consisted of a platform or netting mounted on two long poles that was shaped into an isosceles triangle. This was pulled by animals to drag loads of goods over land. In turn of the travios the wheeled vehicle was created. A wheel enables efficient movement of an object across a surface. The early wheels consisted of axles and wooden disks. Rounded long boards were structured to support the weight of goods. No one is sure which culture started using the wheels first however evidence shows its existence in Mesopotamian around 3200 BCE. Before wheeled vechiles heavy goods and objects could not be transported without water or a mass amount of humans. The structure of the wooden wheel over time transformed into most of the wheels we see today. Transportation grew among countries which allowed trading of goods to be inner twined between cultures.