I have plumbers working on my apartment at the moment. They are replacing all the pipes in the whole building, and also fitting new taps, sinks etc (a pretty big job, especially since they have to leave everything in working order at the end of each day). On the first day (last Friday), they came and cut a hole in one of the walls in my hallway, behind the kitchen sink, to reveal the plumbing. Over the weekend, since I had the hole there, I decided to snap a few close-ups of something that is normally hidden away (and has probably been hidden ever since the building was built all those years ago). The white dust you can see in the photo is the only evidence of the hole that they cut in the plasterboard (these guys are so good that they even painted around the edges of the hole to prevent more dust).