I have yet to see so many at once. Cool shots.
There were more than just those four. There were another two lying separate next to them.
Six in total.
That's the most I've seen in one go as well.
I was surprised to see any at all - although a sunny day the wind had a slight chill and was coming from the east, which was the unsheltered side where the adders were basking.
There were a few common lizards about as well, but they scarpered before I could take a picture.