The hills west of Trondheim give a good impression of the natural environment that Norway offers. This area consists of pine and birch forets, bogs and a few picturesque cottages where hot drinks and snacks are served. When you are very lucky, you can see elg and deer. At the end of the summer and in autumn blueberries, cowberries, cranberries and cloudberries can be found everywhere in this area. More information (in Norwegian) can be found in:
http://www.ntnu.no/vmuseet/nathist/blimedut/bli_med_ut4_NETT.pdfThis area is excellent for making all kinds of walks (1 hour to 10 hours). For suggestions, look at:
http://www.skiklubben.no/2006_Sondagsturen.pdfBuss services to the starting points of walks are mentioned in these suggestions. Bus timetables can be found at:
http://www.team-trafikk.no/ (click bussruter). Buss tickets are sold by buss drivers and cost 22 crowns per single journey.
Maps are included in the suggestions, but they are not very precise. I suggest to buy Turkart Bymarka (sommerutgave) for 80 crowns in a book shop or kiosk. You can also find a map here:
http://www.trondheim.kommune.no/content.ap?thisId=1117611710&language=0 (click sti- og turvergkart - Bymarka)