 The roadway bypasses Brush Prairie on its west side and crosses the Chelatchie Prairie Railroad, before it turns northeast onto 122nd Avenue.SR 503 enters Battle Ground as 10th Avenue and intersects the eastern terminus of SR 502 west of Battle Ground High School.The highway crosses the East Fork Lewis River and leaves Battle Ground to pass Lewisville Park, listed on the National Register of Historic Places and located in Lewisville.