As you can see if you look close in the larger picture, those are post office trucks down that alley. Unclear from the picture, the fence is angled at the corner to create more room, while this metal safety pole is bent towards the fence, like possibly something hit it. This is a well-trafficked alleyway, and not just because of the post office. Just two blocks from Five Points, all kinds of people drive down this alley, or just turn around in it, hence the need for the pole to protect the fence.
Google Maps shows this pole as black and white striped with an “S” or “5” on top, so this is recent, perhaps in anticipation of next month’s Tomato Art Fest. I’ve seen that signature (andee) on some murals, and the style fits. Update: I do believe this is and Andee Rudloff piece.
Located on the west side of the 100 block of North 12th, between Woodland and Forrest Avenues, right at the alley entrance. Easy parking, except on very busy weekends.