I hadn't been to one from 2003 - 2016. But when I walked in I was stunned by:
- obviously quiet/peace. I mean, it's a library! :-) But compared to the library even the footpath is busy with people talking on their phones/earpods now. A dedicated space for quiet was unexpectedly nice.
- lack of "guard" required. No ads/incentive programs/paying-subscriptions/keeping-up-with-Jones-competition. It took me a while to realise that my constant "what do you get from this!?" suspicions could take a back seat. I could relax a bit more, like hanging out with a good friend you can trust.
It is simply a place you can walk into and exist, knowing that you deserve to be here as much as anyone else.
Plus it might have that book you want to read.
I would suggest a classroom. The teacher would consider staring at the phone as rude.