Thanks, both.
Francois: here is the colour version. I've fiddled with it a bit but somehow the b&w appealed more to me: in colour, it's a staircase but in b&w it's rather more abstract. The large cobweb at the lower level certainly shows up better in colour, though! What do you think?
Dick: here is another b&w. I've tried to open up the shadows a bit - is that what you meant? I agree that better lighting would perhaps have made a better shot, but when you're just a tourist, allowed to take snapshots (albeit with better-than-average kit), you have to take what you're given!
Jeremy
(I've also enabled lens profiling on these two, which I'd forgotten to do before; I think it's an improvement)