Version 1 of 2 - this is a large liquid storage tank alongside Wellington Dock in Liverpool - I'm posting this one first and a B&W version next for comparison.  This colour one shows some of the vertical rain-water staining coming down from the top of the tank as well as the horizontal structure with the diagonal stairs across both.

The picture is grainy as I'd left my camera set on 1600 ISO for the last few months without realising it (fool!) and this was taken from quite some distance away zooming in whilst sat on the top deck of a bus, so maybe the focus ain't that great either.  Just use a bit of imagination and maybe it'll all be okay......