This polygon is an index to 1:500,000 scale maps of China, titled [Zhongguo we shi wan fen zhi yi tu], [中国五十万分之一地图]. This map series was originally produced by China, Can mou ben bu, Lu di ce liang zong ju (參謀本部. 陸地測量總局), 1916-1935. This series is part of a large collection of paper series maps held by the Harvard Map Collection and is part of an S.T. Lee grant pilot project to create digital georeferenced indexes for a portion of the paper map collection. To create this index, footprints were generated using the fishnet tool, and metadata were supplied for the individual paper maps by the Harvard Map Collection. After the footprints were created, the shapefile was trimmed and labeled according to the sources. This layer provides an index map that can be used to locate individual sheets and scanned map images when available.