My wife and I totally love Berchtesgaden. I went there first in 2019 because I'm a big World War II guy and I wanted to see where Hitler lived on the Obersalzberg. After one look at the town center of Berchtesgaden that was it. We went back and spent 9 days there from Sept 8-17 last year. It poured rain 7 of the days but we went out anyway, with umbrellas and parkas.
We used public transportation the entire time. Flying into Munich we took the train to Freelassing, switching trains there and then off to Berchtesgaden. We had a slip up at Freelassing because our train to Berchtesgaden was scheduled to be on a certain track but arrived on another track a distance away from where we were waiting. Needless to say, we missed the train but caught the next one an hour later. So, watch carefully the train connections and updates-I think a smart phone with internet access is the best bet to check schedules.
There are several hotels around the area and up in the town center; we stayed in the town center at the Four Seasons. There are others down the hill about a mile away that are good too.
You used to be able to use the walkway from the train station to a trail up hill to the town center, but the walkway over the tracks is closed. There are steps replacing the walkway, but I would not suggest using the steps and trail up hill, simply use the great bus system they have. You can get bus schedules that will practically stop everywhere you need to go. It was better bus service then what I get in my local city here in the states. The red busses stop at the train station and branch out from there.
Be sure and go down the Konigssee lake, bus takes you there. And take the boat ride down the lake to St Bartholoma. Just magnificent!
Be sure and spend a day up at the Kehlsteinhaus also magnificent. You can eat there too.
Be sure and take the Salt Mine tour very interesting (Salzbergwerk Berchtesgaden)
There is also a local museum that showcases the woodwork and all the local arts and crafts from the last 400 years. Pretty interesting too. (Museum Schloss Adelsheim)
On the Obersalzberg is the Obersalzberg Documentation Center worth a visit if you are into World War II and the Hitler terror he caused.
Its a 15 kilometer bus trip down to Salzburg Austria, you can spend the day down there. Beautiful city, tour the Hohensalzburg Castle, the Mirabell Gardens is great too. Salzburg has a great shopping restaurant walking area too.
We took the bus to Ramsau and Maria Gern as well as Lake Hintersee.
There is more in Berchtesgaden, just sitting in the town square and looking at all the mountains surrounding you is enough for me. I'm trying to figure out a way to move from the US to Berchtesgaden. I like it that much!