There's something I do everytime I start a new job. I explore the grounds of whatever place I'm working at, sometimes outside of working hours.
Once it was a huge hospital, once it was a small company in the countryside surrounded by fields and woods, once it was a train station in the middle of a decently sized town (I hated my life it was during covid) and a few other examples
The main reason I do it is to locate the most isolated, least frequently used toilets.
But sometimes I find cool areas outside the office building like parks, parking lots, clearings where I can hang and chill. I often eat there when I can. Yes, I used to eat in the middle of a big parking lot during the summer, there was a nice breeze and the blackberry trees were swarming with birbs.
Storage departments, server rooms (access has become extremely restricted so chatting up the IT guys doesn't always work), archive rooms, disused areas, sometimes entire stories are deserted.
Coming across colleagues who don't often see other people is comfy most of the time they're nice people. Once the cleaning guy stole my work laptop but the company was cool with it an understanding, they even gave me a better one kek.
Rest of the time the cleaning crew are fucking bros. Humble, kind people who are a breath of fresh air in the midst of pretentious normies, pajeets and stacies.
Security staff too, although they're often immigrants. Currently I buddied up to an old lady in charge of booking the meeting rooms, so when I bring her some tea she gives me the schedule for the entire week and I chill there when I know nobody uses it.
I never got roof access because I generally don't keep the same job long enough to know the right people to procure a key.