There are several ways to arrive at and depart from the BER airport. Check out the up to date information at the BER website or the VBB Travel Information. 

Option 1 (train, S-Bahn, U-Bahn; travel time 55 min)

• take train (RE7, RB14, RB22, or FEX) towards Hauptbahnhof and get off S Ostkreuz Bhf
• change to Ringbahn (S-Bahn) S 41 (⥁) and get off at S+U Heidelberger Platz
• change to subway U3, direction of Krumme Lanke
• alight at Freie Universität (Thielplatz).

Option 2 (S-Bahn, U-Bahn; travel time about 1 hr)

• walk to (S-Bahn) train station Flughafen BER – Terminal 1-2
• take (S-Bahn) train S9, direction of Pankow
• get off train S9 at Treptower Park
• change to circle line S41 travelling west/clockwise (⥁)
• get off train S41 at S+U Heidelberger Platz
• change to subway U3, direction of Krumme Lanke
• alight at Freie Universität (Thielplatz).

Visit the Harnack-Haus website for further details.
For further information on public transportation visit www.bvg.de