We stopped in Alfred NY to try out some trikes at The Bicycle Man, went to The Terra Cotta (not that one) for lunch, and parked on a side street. Every parking meter along the street (free on Saturday, fortunately) had an array of house flies parked along the upper edge.
Perhaps this is the best place for flies to warm up before a flight? Was there a recent hatching?
They swarmed off the meters as we passed, then settled back in the same way.