From Frankfurt central station take the S-Bahn S6 (direction Westbahnhof, Friedberg or Karben) to Eschersheim and switch there to bus number 26 (direction Nordwestzentrum). The bus stop nearest to the FIAS (physics building) is called Max-Planck-Institut/FIZ. Alternatively you can go from Frankfurt central station by underground U4 (direction Seckbacher Landstraße) and underground U5 to Willy-Brandt-Platz. Take there the underground U1 (direction Ginnheim), U2 (direction Gonzenheim), U3 (direction Hohenmark, Oberursel or Heddernheim) and switch at station Heddernheim to bus number 26 (direction Nordwestzentrum). Leave the bus at Max-Planck-Institut/FIZ. With underground U1 (leaving Willy-Brandt-Platz) you can also go to Nordwestzentrum, switch there to busses number 26 (direction Im Uhrig) or number 29 (direction Hohe Brück) and leave the bus at Max-Planck-Institut/FIZ. Walk down Max-von-Laue-Strasse until you reach a vivid red coloured building on the right which is the new FIAS building. With underground U8 (leaving Willy-Brandt-Platz direction Riedberg) you can go directly to Uni Campus Riedberg, leave the U8 there and walk to the vivid red coloured FIAS building. With underground U3 (leaving Willy-Brandt-Platz direction Hohenmark, Oberursel, but not Heddernheim) you can also go directly to Niederursel. Walk there some 20 metres in the direction of the underground and turn right onto Kreuzerhohl. After 500 metres you reach the vivid red coloured FIAS building on the left.
If you are interested in detailed routing information, you might want to have a look at the RMV online timetable.
Direct access to RMV routing form (always experimental):
From Frankfurt airport (Terminal 1) to FIAS
From Frankfurt airport (Terminal 2) to FIAS
From Frankfurt central station to FIAS
From the south or west: Take highway A 66 exit Miquelallee and drive in the direction of Nordweststadt/Oberursel. Follow Rosa-Luxemburg-Strasse for a few kilometres until the Mertonviertel exit. Follow Marie-Curie-Strasse and then turn left onto Altenhöferallee. At the roundabout take the left exit and drive down Max-von-Laue-Strasse for 200 metres. The FIAS is located in the vivid red coloured building on the right.
If you get lost, phone +49 69 798 47611 or +49 69 798 47600.