According to Telegraph, http://www.telegraph.co.uk/news/uknews/8724183/King-Arthurs-round-table-may-have-been-found-by-archaeologists-in-Scotland.html, 26 Aug 2011, King Arthur's round table may have been found by archaeologists in Scotland. In fact, the archaeologists have found a "circular feature" beneath the historic King's Knot in Stirling. The King's Knot is a geometrical earthwork in the gardens below Stirling Castle. The design of the Knot that we see today dates from the 1620s, but its central mound could be much older. It seems that some writers going back more than six centuries have linked the landmark to King Arthur. Archaeologists from Glasgow University, working with the local Archaeological Society, found that the round feature on the site pre-dates the visible earthworks.
For a discussion on the King's Knot
see please "The orientation of the King's Knot of Stirling Castel" at