We recently stayed at the Poland Spring Resort and had a lovely evening there. It is from another era and so bringing along a bit of nostalgia goes a long way. There are a number of lodging options and we stayed in the Maine Inn where there are no elevators, so if that is an issue, ask for a first floor room. The rooms were quite large, clean and comfy.
If you have time, visit the historic sites on the property. The old bottling facility, the Poland Spring Museum, is especially interesting. The Maine State Building is also well worth a visit both architecturally and historically. We had extra time to kill so we got ice cream and sat on benches along the golf course and watched a wide variety of golfers with very different golfing skills make their way along the fairways and roughs.
Breakfast was a steam table array of your usual suspects, and amazingly good. Try to nibble a bit of everything.
The staff was lovely and always helpful. They are mainly young adults working for the summer, but stop into the bar for a visit with one of the old-time veteran workers.
Dinner was not offered when we were there so I cannot speak to that. Options in the area are bleak, so if the resort is not to your liking, you will have to go a bit out of your way.
We really did enjoy staying there and would certainly go back for some hikes in the fall.