From Interlaken Ost train to Lucerne then bus to Lugano. 4hrs 51min. From Interlaken West train to Bern, train to Zürich HB, then train to Lugano. 5hrs 09min SFr 119. From Interlaken Ost train to Luzern then train to Lugano. 5hrs 16min SFr 79. From Interlaken, Kursaal line 21 bus to Thun, train to Berne, bus to Bellinzona, then train to Lugano. 7hrs 22min SFr 139. From Interlaken drive to Lugano. 2hrs 23min SFr 30.