It does not include the length of streets in big and medium ? sized cities and highways built for the production purpose at factories, mines, forest areas and agricultural areas.

• 它包括大中城市的郊区公路以及通过小城镇街道部分的公路里程，也包括桥梁、渡口的长度，但不包括大中城市的街道、厂矿、林区生产用道和农业生产用道的里程。