I would like to get to the Vienna international airport from the city of Vienna. The cheapest option, according to the airport website, is to use the S-Bahn. Since I do not live next to the railway station, I will be using the U-Bahn to get to the S-bahn to get to the airport.
Let's say I am departing from
U4 Schönbrunn. Then the website of Austrian federal railways suggests several travel plans:
One of them uses the U-Bahn and S-Bahn combination (the unfolded one) but what confuses me is that it requires only one ticket for 2.40 Eur.
As far as I understand, in order to get to the Vienna international airport from the city of Vienna, I will be crossing a travel zone border. I expected to have to buy two tickets: one at the U-Bahn station and one at the S-Bahn station. The need for two tickets is mentioned at the airport website yet the Austrian federal railway website seems to disagree.
How many tickets do I need to buy in order to get to the airport the way I described? What do I misunderstand?