The Himalayan kingdom of Nepal, a small, landlocked country north of Indian Peninsula, had surprisingly never yielded any definite evidence of prehistoric cultures, though its large southern neighbour, India, has a long prehistoric heritage ? from Early Palaeolithic handaxe cultures in the Middle Pleistocene to Chalcolithic settlements in the Late Holocene. At least the Terai plains at the foot of the Himalayas and the lower hilly regions of the Siwalik Hills should have attracted prehistoric settlers during favourable climatic periods. The present work is the outcome of many years of fieldwork and of subsequent detailed analysis and documentation of the abundant data collected in the field in Nepal. This is a first attempt at interpreting the vast collection of data in a hitherto virgin area.