The total area of Shanghai is 6,340 sq.km. with of the city center only over 600 sq.km.. Industrial areas are mainly concentrated in the suburbs, especially in the outer suburbs. Shanghai still has an area of 100sq.km. planned for industrial construction, and the100 sq.km. land includes pieces of land in Jinshan, Fengxian, Nanhui (Lingang), Baoshan, etc., where the land price is approx. 1/3 of that for the industrial parks in the suburbs closer to the city center. There is a considerable land reserve in Qingpu, Jiading and Songjiang, where the land price is not high compared to that in the suburbs closer to the city center. Similarly, the rental fees of industrial factory buildings are commensurate with the land price and closely related to their locations.