This station is close to the center of Vienna. It offers a train connection to the airport and serves as a U-Bahn stop, too.
To get to the airport, follow the green CAT signs (City Airport Train). The train leaves approximately every 30 minutes.
Wikipedia https://en.wikipedia.org/wiki/Wien_Mitte_railway_station
Address 2a Landstraßer Hauptstraße, Wien 1030, Austria
Coordinates 48°12'20.273" N 16°23'3.288" E