"decided that they would make for Trollesund"

Trollesund is described as Lapland's main port. It is fictional, but like many of the places in the world of Northern Lights it may be based on reality – in this case the Norwegian city of Tromsø (see Setting).

The name trollesund is taken from troll, a Norwegian fairytale monster, and sund, a common suffix for place names in Norway that literally means "straight".