The ancient Mesopotamian civilizations (Sumer, Akkad, Assyria, and Babylonia), reaching back to before 3000 B.C., did not develop or possess the notion of the “cardinal” astronomical directions—N, E, S, and W—until the relatively late date of about 700 B.C., in contrast to the Greek and Hebrew civilizations of antiquity. Instead, orientation was determined by the directions of four principal winds, namely, the “regular wind,” the “mountain wind,” the “cloud wind,” and the “Amorite wind.” In terms of our notation, these could be described as, respectively, a NW, a NE, a SE, and a SW wind or as winds from the northwesterly, the northeasterly, etc., quarters. Even astronomical features were indicated (mainly before 700 B.C.) in terms of the directions of the principal winds. In the Assyro-Babylonian language the same word designated a principal wind and the direction from which that wind blows.
Judging by inscriptions and other finds of archaeological excavations, the most prominent wind was the “regular wind” (NW wind), probably because of the high frequency of that wind (it is certainly by far the most frequent wind direction in the present era). Maps and city and topographic plans were usually oriented so that the NW direction was “at the top,” as N is on current maps. Several of the royal inscriptions say that the walls of the city (often of a rectangular shape) as well as the streets of the city were “opened” to the four winds. These statements are corroborated by archaeological excavations. It seems likely that the orientation was chosen so as to take advantage of the heat-stress alleviating effect of winds.