If you don't want to miss one of the best and most romantic viewpoints in Stockholm, you must visit Monteliusvägen, a narrow walking path on steep cliffs.
Wikipedia (Swedish) http://sv.wikipedia.org/wiki/Monteliusv%C3%A4gen
Address 9 Torkel Knutssonsgatan, Stockholm 11825, Sweden
Coordinates 59°19'14.689" N 18°3'37.466" E