I’ve seen flocks of pigeons flying in a tight-knit formation quite often, but it’s not that common to see a flock of crows flying together. You could hear them long before you could see them, and I do wonder where they were heading!
A little while later, two crows returned and were swooping and diving over the valley for a while.
Not to be left out, the local gull population were also congregating nearby, circling over the fields. Maybe the farmer has put down a seaweed preparation on the soil that’s attracting them….