By train: You can get to Salzburg by rail from most European cities. Salzburg Hauptbahnhof is a 20-minute walk from the city center and the bus station and the suburban railroad station are at the square in front. A taxi to the city center should take about 10 minutes and cost EUR 9.
By plane: There are direct flights from London and other European cities to Salzburg Airport, 4 km west of the city center, but not from the United States. From the United States you can fly to Munich and take the 120-minute train ride to Salzburg (you need to change trains at Munich Ostbahnhof), or you fly to Vienna and take a direct train (150 minutes). Taxis are the easiest way to get downtown from the Salzburg airport; the ride costs around EUR 13-EUR 14 and takes about 20 minutes.