Map showing extent of Doggerland, a vast territory in northwest Europe that was above sea level 16,000 years ago, and the territory's diminishing size as ice melted and the North Sea rose. Illustration by Claus Lunau/Science Photo Library.
Via https://sciencemastodon.com/@ebender00/113606996477811407
There already are multiple other standing stone circles in the UK
Though finding one in Doggerland would be really cool
Yes. Eddie izzard mentioned that Stonehenge was built after strawhenge and stickhenge got blown down by wolves.
WATERHENGE!
Also, a henge isn't a stone circle. It's a ring-shaped earthwork. What we think of as Stonehenge is a ring of Megalithic standing stones (not all standing stones are in a circle incidentally) in the middle of a henge.