Planning a vacay to AK

Will be my first time traveling there.
Totally open about where.
I will be going in August so starting to decide the destination(s).

I am a rockhound so gold panning is a must. Aurora borealis viewing is a must. Also, I would like a train ride.

Hoping there are DUers that will respond with their fav places so I can check out those destinations/suggestions before finalizing plans.

Let me know where to go!!
Thanks in advance.