Shinde: Actually, the Gangetic plain is the main boundary, beyond that are zones of Harappan influence. Harappans may have supplied Bihar and its neighbours with technology. There’s influence up to Jammu and the entire Makran coast and Iran. You find different categories of settlements, all in a symbiotic relationship. Out of 2,000 settlements, we have identified five proper cities. Then maybe half-a-dozen towns like Kalibangan or Lothal, and a network of agricultural settlements, villages, and manufacturing centres like Chanhudaro. Also, a large number of ports and small settlements for exploitation of local resources. There’s a pattern of interaction between the cities and the rest.