The OBB, Austrian Train, stops in Feldkirch and the main station is about a 10 minute walk from old town. You can get anywhere in Austria (or Europe, for that matter) via this station. You can get directly to Vienna (6-9 hours, depending on train selected), Bregenz (45 min), Salzburg (4hrs), Innsbruck (2hrs), and Zurich (1hr 40min)
Liechtenstein Bus has a terminus in Feldkirch, making it easy to get here from that country, as well a Swiss towns just over the Rhine. It stops at both center city and at the main train station, making connection easy. The trip from Vaduz to Feldkirch takes about 45min.
flight to Zürich (switzerland ) rent a car 150 km to Feldkirch or : flight to Innsbruck ( Austria ) 150 km to Bludenz which is nearby Montafon and Feldkirch
a highway connects to Bregenz ( directly at Bodensee lake much culture ) and connects to Bludenz/Montafon which ist starting point fo many mountain-tours
Line 13 from Feldkirch, train station, then Feldkirch, Busplatz to Schaan and on to Buchs, Switzerland, runs every 30 minutes, 3,60 Swiss Franks or 2,40 Euro (tell the driver first witch currency you want to use)
Line 14 rom Feldkirch, train station, then Feldkirch, Busplatz to Schaan and Vaduz