Wyoming Highway 343Wyoming Highway 343 is a north-south Wyoming State Road in northern Sheridan County that connects U.S. Route 14 and WYO 345.Route descriptionWyoming Highway 343 begins its southern end at U.S. Route 14 at Dayton and from there travels northwest. At approximately 4 miles into the route, Highway 343 gently curves northeast as it meets Sheridan County Route 118. Shortly thereafter, WYO 343 turns due north. Highway 343 ends after 5.24 miles at Wyoming Highway 345 southeast of Parkman.