Possibly Carduus crispus
This thistle is new to me though if my ID is correct, it is by no means rare. It was growing in open woodland.
It didn't look at all like the one here: http://www.ukwildflowers.com/Web_pages/carduus_crispus_welted_thistle.htm which is described as 'very spiny'. . .
but it did look like those on other sites such as this one: https://www.hippocampus-bildarchiv.de/tier_8533_Carduuscrispus.htm
It definitely had the leafy blades/ridges/welts (with spines) down the stem but again, they were rather soft and flexible and unable to deliver much punch to the spines.
What drew my attention at first were the broad soft leaves. Although they carried spines, the leaf itself was so weak that they had little penetrating power.
I was next fascinated by the flowers where the green bracts were again soft and wavy rendering them only slightly jaggy. the bracts were tied together by cobweb-like strands, forming an open basket around the opening flower.
The crowning glory was a cooperative hover-fly.
If correct, this plant is commonly known as Welted Thistle (or Curly plumeless thistle) - Carduus crispus.
Does anyone have an alternative suggestion?