This belt has played mainly a negative role throughout Indian history in that it remained relatively thinly populated and did not form the focal point of any of the principal regional cultural developments of South Asia. However, it is traversed by various routes linking the more-attractive areas north and south of it. The Narmada (Narbada) River flows through this belt toward the west, mostly along the Vindhya Range, which has long been regarded as the symbolic boundary between northern and southern India.