King and Pawn Endings - Almost all you need to know

For some reason I thought I had already posted the diagrammed position, yet for some reason I cannot seem to find it in my archives. It is a study by Dedrle from 1921 and its solution contains almost all the essential features of King and Pawn endings. I'm not going to post the solution yet, but if you make the effort to solve it (assuming you aren't already familiar with it) it will help you understand some of the paradoxes in K+P endings. I do show it to some of my coaching groups, but I normally save it till the end, after they have mastered some more fundamental positions. It is White to play and win.