Berner Oberland Region - When to go?

We have never found the Berner Oberland or other mountainous areas os Switzerland "crowded" in the usual sense of that word, even in the height of the season. However, there is a "high season" in terms of accommodation prices, often from the first or second week in July through August. For best hiking on snow-free trails, I suggest you go between late June and late September. We have gone at all of those times and have encountered both rain and sunshine in every month. I wouldn't say, at least based on our experience, that August necesarily has the best weather; we have encountered as much rain and cold weather in August as we have in June or July. In September we have encountered both sunshine and snowfall. At this point I'd say my favorite time is early to mid-July, because the wildflowers are at their best in the higher regions.

There's no reason you can't go in October: fewer crowds, hotel prices cheaper, all the trails will still be open, more scenic as the high peaks get a fresh coat of snow, overall temperature will be a bit colder obviously. On the flip side it does rain more in the summer months.

Summer may have the highest average temps but it does not have the "best" weather IMO[INVALID]summer is rainier than fall. I think September and early October are great times to go. I went early Oct last year and a few hotels/restaurants were closed but enough was open for us. We went on one hike from Murren where the only person we saw was a guy closing up a mt hut for the season. (There were still people on the shorter/easier/gondola served hikes). Spring is not a good idea because trails may still be snow covered.

The Loschberg Hotel in Interlaken is great! Reasonable, nice breakfast, and very helpful staff. Nice small hotel.

We were there last yr in July. Lodging reservations are a must in Summer but the area never felt crowded. We had some rain for part of 2 days out of 5 so we were happy. I would say Sept to be a smart time you do not want it too cold but nice for hiking enjoy, we loved it!

If you think you might like to go about this time next year, or later, you could start watching the weather. Of course there is no guarantee it will be the same next year, but it will give you an idea of the range of possibilities. Right now most of the weather sites are showing cool and rainy the next four days. You can always check the webcams for a picture of what is actually going on there.

We just got back a week ago and had perfect weather and no crowds anywhere. We stayed in Murren and made side trips to Montreux and Bern. Absolutely loved the trip and I would suggest September. The weather was perfect, flowers were still in bloom and everyone seemed quite relaxed.

Thanks for the suggestions. Sounds like a September 2011 trip for us! I was thinking about staying in Murren so that we can do lots of day hikes. We are also planning on going to Gruyères for a couple of nights. Anyone who's been there have any suggestions?

Mürren is a great choice. Are you asking for suggestions for Mürren (hiking, lodging, or what?) or Gruyeres, or both?

Lodging in Mürren and/or Gruyeres. I never seem to have trouble finding things to do. :-)