InterLaken to Bernina Express

I suppose you know that the Bernina Express journey cannot be done as a day trip from Interlaken.
If you really want to enjoy it, sleep 1 night at St. Moritz and another night at Lugano.

Timetables:
http://www.rhb.ch/index.php?id=33?&L=4#splash100
http://www.sbb.ch/en/home.html

May be you have a look at the videos of Glacier-Express and Bernina-Express:
http://www.rhb.ch/Video-Glacier-eng.784.0.html?&L=4
http://www.rhb.ch/Video-Bernina-eng.782.0.html?&L=4
http://www.rhb.ch/UNESCO-Clip-eng.1061.0.html?&L=4

Thanks, I had not realized that I can't do that as a Day Trip :)
May be I'll modify my plan and stay one night less in Interlaken.

Or choose another base. Interlaken is really the worst place for day trips to other places than the Jungfrau area.
http://www.myswitzerland.com/en/home.html