What is it?

This very bad pic of a gorgeous plant is to ask any fellow bloopers if they know what it is. It's got an absolutely glorious mass of these white flowers which were unfortunately blowing in the breeze when I tried to take the pic. If anyone lives in the Craiglea/Comiston drive area of Edinburgh you can see it on the corner of st Ronan's terr and Comiston​ drive. I have a couple of other pics of the leaves if anyone needs them. Can someone help?