1. Early traditional urban form (AD 202-618). Many early cities were planned rectangular walled settlements established primarily for administrative and military puroses. Trade was controlled and limited to designated spaces. Internal walls delimited functionally differentiated spaces, with narrow straight streets linking walled compounds.
2. Late traditional urban form (AD 618-907). It became common for cities to be established for economic rather than administrative purposes. Existing cities also gained commercial functions both on existing streets and in new districts outside early walls. New walls were often constructed to encompass the extended urban area.