Interlaken is a tourist town if I've seen one. When walking the streets, you'll hear English, Korean, Chinese, German, French, Spanish, Japanese, basically every language out there! So if you are looking for a quiet town in the alps, this place is not for you. It is the adventure capital of central Europe: you can hangglide, paraglide, skydive, canyon, kayak, white water raft, bike. And close-by (two train stops away) is the UNESCO-sponsored Jungfraujoch peak (the highest point in Europe!)
Insider Tip:To get to Jungfraujoch from Interlaken OST or Lautrobrunnen, it costs about 150 euros on top of an interrail or eurail pass so be prepared to spend a lot of money!