Away Vienna is Austria's main air transport hub, but there are international airports at Linz, Graz, Salzburg, Innsbruck and Klagenfurt. If you're visiting Austria from outside Europe, it may be cheaper to fly to a European 'gateway' city and travel overland from there. Munich, for example, is only two hours by train from Salzburg. Austria has excellent rail connections to all major European destinations.
Buses are generally slower, cheaper and less comfortable than trains.
Major border crossing points are open 24 hours a day. Steamers ply the Danube between Vienna and the German border town of Passau from May to late September. Tyrolean Airways is the main domestic carrier and operates several flights a day between Austria's larger cities. Austrian trains are comfortable, clean and reasonably frequent. Some ski resorts in Tirol and Vorarlberg can only be reached by Bundesbus or private transport.