Impressive pictures!
Here, further north, it is mainly the Oak processionary that is on the move.
Wherever it is found, everything is immediately cordoned off and warning signs put up. The poison of these caterpillars attacks the human immune system and can lead to many problems.
I hope you didn't get too close to them, because the same probably applies to your caterpillars ;)
!WINE
I knew that these Pine processionary have hair and bristles that can create problems to the health of humans and other animals ... but the reaction varies a lot ... fortunately :) my reaction is minimal, I can get very close to them and nothing happens ... only when I accidentally touch them, like I did while recording the video, the touched place starts to itch and slightly burn. It didn't last long though, so it's ok, the price paid for the video wasn't too high.
But the next time, who knows ... this kind of reactions can change in time, so I think I'll let them be next time ... unless something really extraordinary, that just has to be recorded, happens in front of my eyes :)
It seems that here in my area the Pine processionary and the pine trees exist in a relatively good balance, I see some nests here and there and the trees are still prosperous.