The ways to reach the Apartments of Riemergasse:

From airport Vienna (Wien-Schwechat):

Take the CAT (City Airport Train) until Wien Mitte, there take

- either the Underground / Metro U3 (in diretion to Ottakring)
  for 1 station to Stubentor > exit Wollzeile, than the first
  street on the left side.
- or walk across the Landstraßer Hauptstraße and Wollzeile.

www.cityairporttrain.at

By train:

From Westbahnhof (west railway station): 
With the Underground / Metro  U3 until  Stubentor (in direction of Simmering), exit Wollzeile, than the first street on the left side.

From Südbahnhof (south railway station):
With tram No 67 1 station to Underground /Metro station Südtirolerplatz. Take the U1 until Stephansplatz (in direction of Leopoldau) and walk 300m across the Singerstraße, left into the Riemergasse.
www.wienerlinien.at

By car:

From south (Südautobahn A2): 
In direction of Zentrum until Uraniabrücke, left across the Ringstraße until to Gartenbau-Kino > Liebenberggasse > Seilerstätte > Singerstraße, right to Riemergasse.

From west (Westautobahn A1):
In direction of Zentrum across Schwarzenbergplatz and Lothringerstraße to Johannesgasse > Schellinggasse
> Liebenberggasse > Seilerstätte > Singerstraße, right into the Riemergasse.

Routenplaner (Google-Maps)