Possibly Centranthus ruber, but can I just throw Saponaria officinalis into the ring (aka Soapwort, Bouncing Bet etc etc etc) - I can't find any in my garden to check (I weeded it all out last week but there'll be plenty more in a month's time) but my Keble Martin looks pretty similar.
Well worth throwing in Dove, strong contender.
I hadn't seen it like than. Mine doesn't come up in a clump it puts up a shoot here and another one there
It sneaks into this garden under the fence from next door as runners but when we first arrived here it was in large woody clumps. On the other side of the city there's a large area completely covered with it - pretty and the bees like it, but it does like the soil here so has to be controlled.
Valerian officialis (spelling?) drops on a cat's toy makes them go all "gooey"!
It was Valerian, so many thanks for everyones help, I recognised the same in Granada over this weekend where its out in flower and my friend identified it for me
A bit more advanced over there