 As they fit better with the mountainous topography of Austria, "Schnellstraßen" often serve as an autobahn substitute.For example, the main link between the Austria's westernmost state of Vorarlberg and adjacent Tyrol is entirely provided by the "S16 Arlberg Schnellstraße", including the Arlberg Road Tunnel completed in 1979.Since 1997, the use of all "Autobahnen" and "Schnellstraßen" requires the purchase of a vignette (toll sticker) for passenger cars up to 3.5 tonnes or a "GO-Box" (electronic toll system) for trucks and buses.