Södermalm: Katarinavägen - Kvastmakartrappan
The north east of Södermalm will offer you a mix between the modern and the old city. From the hills you will have a nice view of Gamla Stan, Skeppsholmen and Djurgården.
Try this promenade during winter and you will experience Stockholm covered in ice and snow.
Södermalm, Slussen, Katarinavägen, Kvastmakartrappan, Katarinagångbro, Fjällgatan, Lotsgatan, Fåfängan