The traditional view put forward in Norwegian geological discussions has been to draw the links between the Trondheim region and the coastal area south of Bergen over the Jotunheim region. On the other hand an essential difference has been claimed to exist between the Trondheim region and the Jotunheim region. In actual fact there are a number of circumstances which show that the connection between the Trondheim region and Sunnhordland does not run via the Jotunheim region, but via the Devonian synclinal area of Vestlandet.

On this view the Caledonian mountain range forms a great are pushing into Central Norway, having its convex side towards the southeast and to southward passing over into an are with its concave side to the southeast. Such an arcuate mountain chain would provide an explanation of the complex folding systems that we encounter in the chain. In the following paragraphs I shall discuss featurcs which throw light on the relationship between such an arcuate mountain range and the geology of Norway.