Except for the route between Kobe Sannomiya Station and Fukuchiyama Station, every bus service has been operated since the 1980s; the time needed to cover the distance has become shorter and shorter as the expressway network has been extended, although the number of bus services hasn't significantly increased.
神戸～福知山系統を除き、いずれも1980年代から運転されている路線であるが、大幅な増発こそないものの、高速道路網の延長に合わせて、所要時間の短縮を繰り返している。