The County Line Trail is a multi-use trail bordering Kittitas and Chelan Counties, connecting the Teanaway Ridge trail and to Miller Peak.
The official trailhead is quite small and hard to get to, but the upper section is usually utilized to allow hikers to complete a loop that includes Miller Peak and the Iron Bear overlook by starting at either Iron Bear - Teanaway Ridge, Teanaway Ridge, or Miller Peak trailheads.
Another section of the County Line Trail (1226.1) is found further west. It leaves from the Beverly Turnpike trail and a connection to Navaho Pass can be made, but the second half of the trail is difficult to follow.
Consult a map when planning your outing.