Our family is to meet up with a family reunion the end of June in Stockholm...we want to travel to three places before hand. Should we take a train or fly to Copenhagen? We will fly into Munich from the states.
6 days is barely enough time for three cities. Even if you fly between destinations (and I don't think Interlaken has much of an airport, if any), you will still spend most of your travel days in transit of some kind. You will have, at best, 1 full day to see each stop. Also keep in mind the jet-lag you will experience upon arriving in Munich, which will limit your initial sight-seeing activities. Because your flight lands in Munich, perhaps you might want to consider spending most of your time there, with maybe a day or overnight trip to the Bavarian Alps?
Tom is giving good advice. If you have not already done it, you may find it helpful to study a map that shows the distances between these locations. Then think about the travel times needed to get to your destinations and you will have a better idea of what is realistically doable, and at what cost in money and stress.
That is a very ambitious schedule and you will spend a lot of time traveling. I think you have to fly into Copenhagen if you only have 6 days. It is going to take you about 8 hours to travel from Munich to Interlaken by train. It is more than 15 hours from Bern to Copenhagen on a fast train ... Also keep in mind that Stockholm is about 5 hours from Copenhagen.
Personally, I would suggest that you drop one of the places.
Wow. I would really consider dropping Gimmelwald. It's way south of Munich, Copenhagen and Stockholm. You would be looking at a 20hr. train journey with 5 changes (I looked it up on www.bahn.de) to get to Interlaken from Copenhagen. THEN, your still looking at a 25 minute train ride from Interlaken to Lauterbrunnen, a 20 minute bus ride from Lauterbrunnen to Stechelberg to catch the gondola up to Gimmelwald. Figure an additional 60-90 minutes overall. Then, you need to go back the other way.
Actually CityNightLine does operate a night train from Basel Switzerland to Copenhagen. Basel is only 2 hours away by train from Interlaken. But even then, it's still a tight itinerary.
The answers you have received are correct.
You have chosen destinations too far apart to cover in the limited time you have.
Experienced travelers would allow at least 10 days to visit all these towns.
Go to your library and look at a map of Europe or search the internet for distances between points.
Try howfarisit.com for distances in Europe.
Six days is barely enough time to get a good look at Copenhagen and Stockholm. I suggest forget about going to other countries in this trip. Is it necessary for you to fly to Munich ?