Norfolk has a Neolithic henge circle at Arminghall, built c. 3,650-2,650 Cal BC (4440±150), radiocarbon dated from charcoal from a post-pit. The henge is orientated on the mid-winter sunset, so that the sun, when viewed from the henge, seems to set down the slope of nearby high ground, Chapel Hill.
http://www.megalithic.co.uk/article.php?sid=4797
http://www.megalithic.co.uk/article.php?sid=4797