Station Landstrasse, served by lines U3 and U4, is the large transfer station. Take the U4 line to the Hütteldorf direction. From the Landstraße stop, pass over the Stadtpark stop and exit at Karlsplatz stop. The Vienna U-Bahn operates daily between 5 am and 12:30 am.
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How to get from Vienna Airport to the Kaiserhof hotel by public transport? Train from the airport to the Mitte Vena central transport hub, continue by metro two stops to Kaiserplatz, and five minutes walk to the hotel. The fare is about 10 euros.