Pretty in pink

Today we drove up to the other side of Sheffield to a place called Wyming Brook. It was enchanting ... just a single path through woods full of birdsong (and the occasional glimpse of the birds), hardly any other people and, all the while we were walking (or, in Jan's case, trundling) we could hear and see the loveliest brook burbling away below us. Lots of butterflies, as well. I thought I wouldn't inflict any birds or butterflies on you today, so here is a representative of the flora we saw.

Again, if anyone knows its name, I would be delighted to know it.