On Google Maps, Quartz Creek Trail is shown as NF - 5640. This information has been verified by both the United States Department of Agriculture (https://www.fs.usda.gov/recarea/mbs/recarea/?recid=18054), and AllTrails.com (https://www.alltrails.com/explore/trail/us/washington/quartz-creek?mobileMap=false&ref=sidebar-static-map).