First set of 4 sets of map pictographs for U.S. national park maps. PD US Government - National Park Service, U.S. Dept. of the Interior
rest of set:
http://openclipart.org/media/files/johnny_automatic/6754
http://openclipart.org/media/files/johnny_automatic/6757
http://openclipart.org/media/files/johnny_automatic/6765 NPS地圖像形文字第1部分 cartography、externalsource、map、park、pictograph、sign、symbol 製圖、外部源、地圖、公園、象形文字、標誌、符號 資料來源:openclipart ( https://openclipart.org/ )