image/svg+xmlOpenclipartcannon 12008-01-24T03:42:29symbol for U.S. national park maps. PD US Government - National Park Service, U.S. Dept. of the Interiorhttps://openclipart.org/detail/11589/cannon-1-by-johnny_automaticjohnny_automaticcannoncartographyexternalsourcemapparkpictographsymbol