I think this is either landscape or architecture. Taken in a hidden spot at the bottom of Box Hill in Surrey. I knew it was there, but I drove past several times before I found it...
Cool shot, Lesley. It has a surrealistic feel about it, with the glassy smoothness of the water on the left contrasting with and indeed penetrating the roiling water on the right. And its impossible to determine the scale, since there is nothing to reference the size of the stones against. And I like how the stones flow up and into the upper right corner of the image. Very nice composition.
I like this for all the reasons that Brian has already listed (damn him, I was just too slow! ). I can think of nothing more to add really other than to say it is a wonderful shot Lesley.
Um... I know I'm taking a break from cleaning litter trays, but for the moment I can only think of Cat's Protection League. To be fair, I used to home check for them years ago. Er... got it now! Polariser! I used to use one on my film camera, but I went off due to the over darkening of the corners with a wide angle lens. I think I used a Neutral Density filter here to get the longer exposures. I tried some at several seconds, but the silky effect didn't work well with this little river