Spatial structure and relationship between ports and port cities along the Maritime Silk Road

![CDATA[The economic development of the coastal areas has promoted the construction of the port and led to the expansion of the port city. This study selects 35 port cities along the Maritime Silk Road to develop a Port-City Relationship Index (PCRI) from the analysis of port city development stage and spatial structural change. Three types of port city spatial relationship models are proposed: centralized port city, marginal port city and separated port city. We compared the distribution and variation of PCRI values over four time periods for the 35 port cities. The results show that the ports in West Asia, Africa and Europe are basically mature, and the changes of PCRI values are relatively small. The ports in Southeast Asia and South Asia are still in development stage, and the value of PCRI varies greatly. As the city develops, the dependence of city on the port will gradually decrease. The spatial relationship between the port and the city will generally evolve towards the marginal of the port formation (PCRI=0.6) and eventually remain convergent and stable. In the end, the effect of most ports on urban spatial structure will gradually stabilize.]]