High Havermonkey
16d you are looking for a common word used for plasters. I haven't got 25ac yet.
I've now read through the undefined theme words and only got two, which surprisingly I was able to enter into the grid (they may be wrong).
I'm hoping I've understood the theme and assume most of the answers are places, but I've never understaood what human geography means.
I think I know the five town mentioned above, but cannot see which it relates to. I have numbered them 1-37 for my convenience.
I could do with a hint for 11d and 3d.
I have to go and sort out my Hot Cross Buns now to put them in the airing cupbopard to rise overnight, then there is the BBC4 Irish/New Zealand thriller. I think I'll still be working on this tomorrow or Monday. I've some gardening to do as well.