Hazard areas are King County's own coal mine hazard polygons (1990 Sensitive Areas Ordinance), shown as published. Cities such as Issaquah, Renton and Newcastle may keep their own maps; check with them. Mine maps are scans from the Washington Geological Survey's Coal Mine Map Collection, placed by the Survey in 2016 from section corners and railroads (typically 4 control points). We use the Survey's placement as published; each map's fit error, as reported by the Survey, is listed with it. The amber layer is the dark line work of the original sheet, including title blocks and survey lines, not only tunnels. On the maps we checked, 70-95% of the drawn line work falls inside the county hazard area. 3D views lay a map's workings at the depths and dips written on the sheet, under USGS lidar terrain. Assumptions are stated inside each view. Not covered: mines whose maps were never placed (about a third of King County's sheets), unmapped workings, and anything after the map's survey date. Absence of a mapped mine is not evidence that no mine exists.