I was walking across the Carfax, which is the central - not a square exactly, because it is round - space, say, in town, when I suddenly became aware of a cheeping sound overhead.
There were about a dozen swifts (I had to google swallows, swifts and house martins to make up my mind) buzzing around in the bright sunshine, hoovering up the insects at a great rate.
I think I was only one of all the people milling to and fro who noticed them.
So I paused and watched them for a while, swivelling my head to follow their acrobatic manoeuvres between the rooftops and the trees, until I had to stop because the sun was making my eyes water.
I didn't bother trying to take a picture with my phone. They were too small, too fast, too unpredictable in their flight patterns.