During mid-19th-century overland trails were very popular means of travel by immigrants. The immigrants began to settle North America and the region west of Great Plains. After the Mexican and American war in 1849 mass immigration started again. Two major wagon networks that were famous among the migrants were the Oregon Trail and Santa Fe trail. The Santa Fe trail was the southern trail. The Oregon trail was Missouri based route. According to estimates between 1843 and 1869, at least 500,000 emigrants used the Missouri based trails.
At the beginning of the Neolithic Revolutions, towns were created near rivers, as a source of water for their crops. <span>It was D, the River Valley Civilization!</span>
