Extraction and Digital Translation of Urban Spatial Elements Based on a Series of Historical Maps

Figure 8

Bridges on the Wall River ((1) Peace bridge; (2) Shanxi bridge; (3) Chengdu bridge; (4) Yingkou Road; (5) Hubei bridge; (6) Xinhua bridge; (7) Hebei Bridge; (8) Yaohua bridge). (a) The number and location of bridges in maps over the years. (b) The locations of bridges on the historical map (use the 1951 map as the basemap).