Aww man...so envious of you! We spent 10 days there back in 2013. (my parents used to live there) What a stunning place. Get ready to spend serious coin on food though. We visited during the era of Subway's famous "$5 foot long" promotion. Well...in Alaska that $5 foot long was running about $12. We really had no intention of eating at Subway in Alaska, but after our first night dinner priorities changed. We ate at a traditional salmon bake and for the 8 of us the tab was over $400. That was with 4 kids and NO alcohol consumed by anyone in our party.
It was also much warmer than what I was prepared for...several days of temps in the low 80s. Very few places have AC because it's seldom needed. We had a couple of uncomfortably warm nights for sleeping.
We arrived in Anchorage and my first impression was "meh" - Anchorage is a large city of over 250,000 people and it didn't feel that much different than around here. We rented a car, got about oh, 2 miles outside the city on one of the very few highways in Alaska and my wife was like "um..there's a moose in our lane ahead." Suddenly we realized we weren't in the LSV of PA any longer. We probably didn't go a mile farther and a black bear came lumbering across the road...
Enjoy your 18 hours of daylight! Anchorage currently has a sunrise of 5:00am and sunset is quickly approaching 11:00pm. It takes a bit of getting used to it getting dark after midnight...