Adelboden and interlaken - trip in september

Welcome to the forum, swisstravel. I think you should do some research first, to find out what your interests are. There's so much to see and do in these regions, that it's very hard to give random advice. Please browse the forum and take a look at these day trip and hiking trail overviews. Many trips can be planned with the aid of the timetable. I hope that gets you started. You're welcome to get back with more specific questions!