archaic humans of the Middle Paleolithic. It would remain this way until about 50,000 years ago, when discoveries of a marked increase in the diversity of artefacts found were associated with modern human remains. Geographical context The Soanian culture is in the Western part of the Sub-Himalayan terrain, stretching between river Indus and Yamuna. This area is the major producer of Soanian artefacts. The occurrence of this technological culture has been correlated to the prehistoric geographical changes in the region that allowed prehistoric humans easy access to raw materials. This view is often hypothesized to have been the result of boulder conglomerate formation in the Siwalik region between 0.7 to 1.7 million years ago. These formations are collections of large rocks made of small fragments that have been deposed through tectonic processes, they can look like levitated ranges or hills. The tectonic process also formed rivers and fluvial systems that carried and collected raw materials, such as distal alluvial fans and proximal distal braided stream systems. In the Siwalik region, the dominant raw materials available are quartzite pebbles, cobbles, and boulders. From 1.6 million years ago onwards, the existing boulder conglomerate formation saw more changes that further contributed to easy access of raw materials for local ancient humans. Further tectonic movements and erosion saw the Siwalik fluvial courses altered –developing more complex river systems, and deposits that carried and collected sediments. This also contributed to new drainage systems formed by new alluvial conditions in the South Siwalik region. These new developments allowed for the easy access of materials and prevents the need for long-distance transport. This geographical context the Soanian culture developed from is known to scholars as the Post-Boulder Conglomerate Formation period. Scholars of the single interval period argue Soanian tools are developed due to the movement of the Harappan culture. During the mid-Holocene global arid phase, when water supply starts to dry up across the globe, the Harappans who were originally around the Indus valley mostly shifted to the sub-Himalayas in search of water sources. This led to the diminishing of the broad trading system of resources within the civilization that included materials like metal. As a result, Harappans started to manufacture tools using stones that are later discovered to be Soanian tools. This period has been viewed as a process of deurbanization of the Harappan culture, where they began to decrease in size, turning into smaller village-type