On a rainy day in Trondheim you should definetely try out indoor climbing. This is an activity I really enjoy and I’m sure you will like indoor bouldering at Trondheim Klatresenter too. It is funny, challenging and a great work-out. It can also be very social and is an affordable activity, even for students. Definetely recommended!
Pål Mikalsen Rolfse, Monkey Brew