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. Rental car companies have branches in main cities. Roads are generally good, but sufficient respect should be given to difficult mountain routes. Austrians drive on the right, so you should seriously consider doing likewise. Bicycles can be hired from over 160 railway stations and returned to any other station with a rental office.