image/svg+xmlOpenclipartbuoy2008-01-24T17:51:14nautical symbol for U.S. national park maps. PD US Government - National Park Service, U.S. Dept. of the Interiorhttps://openclipart.org/detail/11633/buoy-by-johnny_automaticjohnny_automaticbuoycartographyexternalsourcemapnauticalparkpictographsymbol