Questions & Answers about Við dáumst að útsýninu frá fjallinu.
Why is the verb dáumst and not just dáum?
Because the dictionary form is dást að, not dá að. This is a middle-voice verb, and the -st is part of the verb itself in this meaning.
So við dáumst means we admire / we marvel at.
For learners, it is best to remember the whole pattern as dást að + dative.
Is að here the same að that means to before an infinitive?
No. Icelandic að can be more than one thing.
Here, að is a preposition, not the infinitive marker. It is required by the verb dást. With this verb, að introduces the thing being admired, and that noun goes into the dative case.
So in this sentence, að útsýninu is not to view or anything like that. It is the prepositional phrase that goes with dáumst.
Why is it útsýninu?