There were many ancient roads and routes referred to in various ancient texts and the travelogues of pilgrims through India, connecting to different countries and regions across varying terrain. One of which was Uttrapatha, a route mentioned in Buddhist and Brahmnical texts. It connected central and western Asia through Kabul, and southern Asia onwards from Tamralipti and Tamluk in Bengal. The Uttrapatha passed through the lower Himalayas and Indo-Gangetic plains. We find Ashokan inscriptions datable to 3rd century BCE along a larger stretch of this route. During the medieval period this was known as Sadak-e-Azam and Badshahi Sadak, or the Grand Trunk Road in the colonial period mostly followed the same route, with some deviations. The recent research of the author of this presentation has focused on tracing the archaeological sites along these ancient and medieval routes in view of considering the proven significance of Uttrapatha as the foundation of modern day highways across parts of India. During the course of this work, an ancient causeway (remains of GT Road), about 4 km long made of large sand-stone blocks, and across a probable ancient ferry point of the Sone River has come to light. This causeway, mentioned in British records, apparently predates the colonial rule, and seems to have been constructed during Mughal period, or even earlier. This paper aims to elaborate on the significance of a potential ancient Uttrapatha route crossing the Sone River.