What to do in Stockholm at 5AM?

The night train arrives into Stockholm at 5:05AM and I can't get into my hostel until 14:30 so I am looking for ideas to kill time on a April Saturday morning until the museums open. This will be my first time in Sweden.

I saw a similar question asked a while ago but Im looking for something to do or see early in the morning and not wait around the train station, I'll see enough of those on the rest of the trip.

Where would be a good place to watch the sun rise?