Everyone has their own pace, and I thought I’d share what we accomplished on our trip in June and why I proposed this whirlwind tour:
“Day 1: train to Lauterbrunnen, transfer to train to Wengen. Gondola to Mannlichen. (1 hr 55 min journey). Different gondola down to Grindelwald Terminal. Train to Grindelwald. Walk through town to First station. Gondola up to top. First cliff walk. Lunch with a spectacular view. Gondola back down. Walk back to Grindelwald station. Train back to Lauterbrunnen. Gondola up to Grutschalp. Train to Murren. Funicular to Allmendhubel. Explore Murren. Gondola to Gimmelwald. Gondola down. Bus to Lauterbrunnen. Dinner. Train back to Bern.”
We took the 7:45 train to Jungfraujoch and we’re back down to Grindelwald by lunch time (1:00 ish). This is why I think you could do the 1:55 journey from Bern to Mannlichen in the morning. I’m not saying you’ll have time to smell the roses!
After a leisurely lunch in Grindelwald, we went to First and did the thrill walk. Then we took the train back to Kleinne Scheidigg and on to Wengen and were back before dinner. Plenty of time to get across the valley to Murren if we had wanted too. But we had 6 days to explore. We did the Grutschalp/ Allmendhubel/ Murren/Gimmelwald loop in about 3 hours the next day, including playing at the playground and a stop for hot cocoa at Allmendhubel and lots of shopping in Murren. We had lunch in Lauterbrunnen that day.
I’m not the type to recommend whirlwind trips normally, but with only 2.5 days in such an area, you really don’t have enough time. If you want to linger, you have to be very selective.