What was a major reason the cities of babylon, harappa, and kiev became important centers of civilization?

Localization of the important river banks and flow of production benefited the agriculture and economy of these cities.

Explanation:

Babylon: Military expeditions were carried out after harvest, usually on an annual basis and especially in the first millennium, when farmers could become soldiers. Minerals (copper, tin, silver, a black stone called diorita, etc.) were available in distant areas, so campaigns had to be considered very carefully so as not to be expensive or to leave cities at the mercy of other enemies. Trade then began to be practiced. In texts from around 19000 BC, there is evidence that trade is beginning to be professional and capitalist, with business being carried out by vessels along the Euphrates and the Persian Gulf and regular donkey caravans to Anatolia (modern Turkey).

Harappa: The harappeans also lived by a very important river, the Indus; For this reason, they have long been known as peoples of the Indus Valley, where Pakistan is today. The exhausting work of many archaeologists has led to the discovery of admirable rubble dating back to the Bronze Age; These ruins date from 4500 years ago.

Kiev: Located on the banks of the Dnieper, about 2,290 km long, Kiev is the capital and largest city of Ukraine. Its territory is in the north-central region of the country, and is one of the oldest cities on the European continent.

Despite the development found in the city, Kiev has always been a territory that has gone through ups and downs. It is among the oldest cities in Eastern Europe and was founded in the 5th century. At that time, the Ukrainian capital was used as a trading post in the region of the first Slavs who inhabited eastern Europe. Over time, the city developed and became a major center of Eastern Slavic civilization. It became a cultural and political symbol, between the 10th and 12th centuries, of the Principality of Kiev, also known as Kievan Russia.