The Alps appear many times throughout Frankenstein, each time connecting the setting to the larger themes that are presented in the novel. More specifically, in my opinion the Alps act as a mirror of Victor's inner life and feelings. The first time the Alps are mentioned is just after Justine's exicution as he is traveling into the mountains it states "As it was, I was somewhat interested in the scene; it sometimes lulled, although it could not extinguish my grief." (Vol. II Chapter I) I think what Shelley is trying to convey through this quote is how the natural landscape brings some peace and possibly distraction from Victor's sorrow. 

A bit later in the same chapter Victor enters the Valley of Chamonix when he notices a landscape shift, "The valley is more wonderful and sublime, but not so beautiful and picturesque as that of Servox, thorough which we had just passed." (Vol. II Chapter I). I think this shows Victor's self alienation in a way. He is saying that Chamonix isn't as pretty as Servox but because its bigger and more powerful it speaks to him more. It seems like this shift in emotion proves that Victor's emotions are still very heavy and the sublime scale of the Chamonix reflects his inner struggles. 

The Alps then become the setting for the most important event in the novel, the confrontation between Victor and the Creature. Shelley was intentional in her descision to make this scene on the highest mountain in Europe. The glacier and the mountain's, as Victor describes, "tremendous dome" of Mont Blanc reflects the relationship between Victor and the Creature, unstable and terrifying. I think Shelley's repetition of the Alps throughout the novel act as much more that just scenery and conveys the message that mirrors how Victor truly feels. When you're in the mountains you can't escape them, I think they act as a constant reminder to Victor that he cannot run from his consequenses. 

For Shelley's early readers the Alps would have carried the same meaning. Not long before this era the Alps had been seen as very dangerous and were to be avoided. But by the early 1800s, it shifted into being a symbol of awe and inspiration. We see instances of this from writers like Byron Shelley's "Mont Blanc" as well. 

 The Alps shown above photo found on Bing public commons