I grew up in Bangor but have lived in and visited many other cities. Be prepared for everything but bars to be shut down by 10 pm. This is the thing I hate the most about this town. On Sundays, the mall closes at 6 pm. As a night owl who doesn't drink, Bangor is pretty lame. I miss the convenience of 24 hours grocery stores and being able to get fast food that isn't McDonald's past midnight. It is great in the summer tho...

One must do: Eat at Dysart's! They're open 24 hours so we used to go sit and drink coffee there when there was nothing else to do. Also they have the best home made pies, cookies, and breads. They're a truck stop, but the food is fantastic!

Also, I hope you have your own car. The public transit in Bangor is a joke. It doesn't even run on Sundays and I think it stops around 8 pm at night. You pretty much have to drive every where in Bangor. There are no bike lanes so biking is very dangerous (plus bikers here do not follow the rules of the road). And there are a lot of main roads with no sidewalks making it very hazardous to walk to your destination