Describe the trade routes in the early river valley civilizations

A river valley civilization is an agricultural nation or civilization situated beside and drawing sustenance from a river. A "civilization" means a society with large permanent settlements featuring urban development, social satisfaction, specialization of labor, centralized organization, and written or other formal means of communication. A river gives the inhabitants a reliable source of water for drinking and agriculture. Additional benefits include fishing, fertile soil due to annual flooding, and ease of transportation. The first great civilizations, such as those in Mesopotamia and Ancient Egypt, all grew up in river valleys. Tigris River flourished near Mesopotamia civilization and river nile flourished near civilization of Egypt.

the northwest ordinance of 1787 guaranteed basic rights for settlers and banned slavery there.