Taking a walk along Katarinavagen offers some of the best views in all of Stockholm. Start the walk right by the McDonald's near Slussen and follow the curved road all the way up to the top of Sodermalm! From there you have a great view of Old Town, Skeppsholmen and Djurgarden. You could combine this walk with a stroll to Nytorget Square in the heart of Sodermalm, then walking along Gotgatan until it brings you backto Slussen, Gamla Stan (Old Town) and the Central part of the city. From Slussen, (with no stops and at a casual pace) the entire combined walk should take just over an hour.
You also have the option to combine scenic Fjallgatan into your walk as well...the choices are limitless!
APPROX 20 MIN WALK FROM T-CENTRALEN