Unknown flower, London WWT, May '17 (1 Viewer)

I took these photos figuring I had a good chance of identifying it myself but my efforts are proving fruitful as I don't really know where to start!

I thought it was some sort of orchid but I'm not having any success Googling down that route. So I am calling for help from BirdForum...

Taken at London Wetland Centre (WWT) back in May of this year

Thanks
Mat

Surprised you couldn't see the flower is a type of Iris as it's such a familiar plant from gardens as well as in the wild. This isn't a native species + can't see the foliage but looks like I. sibirica to me.

Oh, an iris. Well, well, well. Thank you.

In my defence (not that it really is one) I live in a flat with no real garden. I also think I've had a major blind spot when it comes to flowers, going back many years