More suggestions,
go somewhere near to where you live. there's usualy a magic/prehistoric/ancient site not far away. If not, create one.

I live in Derbyshire now so I've mostly been going to Arbour Low for the solstice. Recomend this site. not busy like Nine Ladies/Stanton Moor. one can camp descreatly at Arbour Low. A truly marvelous henge monument. designed for the job.

But last year I was up a-top Mam Tor. Castleton, Derbyshire. Iron age earthworks, bronze age mounds. and high up.

I know both Meg and Castlerigg. I lived in Cumbria from about 1984-91.
Funny you should mention it cos I am considering a solstice visit to the lakes. Castlerig came to mind. but after what I just read, it sounds to busy.

I recon Long Meg and her Daughters will be as grand as owt.
did you know ? the outlying stone, Long Meg, is perhaps of a different date to the circle + also it's of a different rock. Check out the rock art on it.

john