Washington State Route 221 ( SR 221 ) start at an intersection with SR 14 in the unincorporated community of Paterson . After leaving Paterson the highway travel north through rural farm land as a two @-@ lane highway . A few minor roads are intersected before the roadway turn to the west after about 17 mi ( 27 km ) , before turning back to the north . After the highway resume its northerly course it climb into the Horse Heaven Hills , gaining a passing lane through the uphill segments , before finally terminating at SR 22 in south Prosser .