These wasps were locked together under a tree in my garden today, in Scotland. They seem very large to me - maybe over 2 cms, and quite chunky. I have a phobia of wasps, so feel pleased I got this photo! But they looked different to usual wasps to me. Firstly, they were so big, secondly, so yellow - almost fluorescent, thirdly, they didn't have a tiny waist as far as I could tell, and the black stripe just behind their thorax was very shiny and furry. There were black dots on the abdomen and a yellow spot just at the start of the wing, the rest of the thorax was black, and one yellow stripe around their head.
Any information would be greatly appreciated, including whether this is a common sight at this time of year. Thanks.