Re: The Jail
At a glance, it's obvious going through the front is the worst possible choice. There's always a lot of activity. Lots of eyes and hands and feet about. Even with a distraction, it would be the main focus as it seems the main entrance and egress.
The side door onto the street isn't as well guarded. But it's visible from the street. And easily visible from the front if anyone just peeks around the corner. Entry is possible there, if you're quick, quiet, quiet, quiet, and more quiet. Also quick.
The back is a bit more promising. Again, not as heavily guarded. And while still visible from the street, it's not as accessible from the side guards and certainly not from those at the front entrance. You both notice there is a bird's nest built above the door. It's odd but not necessarily alarming. There's just something about it that draws both of your attention.
The last possibility that you can see is the roof. There are two crossbowmen walking the roof, mostly watching the street. They check in by leaning over and yelling down to the guard station at the front, but only at what appears half hour intervals. Otherwise, no one seems to pay them attention. They aren't visible from the street the entire time. But you would have to hit them, again, quick and quiet.
You can't rule out that there is a sewer line entrance. But nothing you can observe from up here is able to give you much to go on.