When you get the chance to visit Stockholm, you should go up to Monteliusvägen, which is in Södermalm. It is a great viewpoint from where you can see a lot of the city.
Panorama of Stockholm from Monteliusvägen
You have a great view over Gamla Stan, Östermalm, the Stadshuset and Lake Mälaren. On a sunny day you can watch boats travelling from the Baltic Sea to Lake Mälaren or into the other direction because one of the locks is directly besides Gamla Stan. You can also see the houseboats beneath you and some of them are hotels where you can stay when you want to.
Monteliusvägen is a great place to see a big part of Stockholm.
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