 The specific state in which "Highway Patrol" took place was never  actually given and was in fact meticulously avoided. Most fans of  the series presumed it to be California because the state was  obviously quite large, had a generally pleasant climate, and  featured mountains, desert, and seacoast. An exchange in this  particular episode further perpetuates the "mystery". When Ann asks  Dan (who is posing as "Mr. Daniels") if hes from the Lakewood area  originally, he says "No, Im just passing through. Californias my  state."