Swift - Apus apus

I got off the bus before my destination when I spotted a sky full of Swifts. I have seen them before, but was always too busy, Today I thought "..what the hell..". So I spent 15 mins or so leaning up against someones's wall pointing the camera upwards. It was of course not at all successful and my arms started to hurt so I gave up and went on my way... this was the best I got I'm afraid.
So I went off to the bus stop and got buzzed by one!!! They were just toying with me :)

Nice shot nonetheless Louise, haven't seen a swift in ages.

There are lots of patches of them over central Reading - older houses and lots rented so the rooves haven't been filled in.