A Standing Stone above Finlaggan. This structure and other standing stones on Islay probably pre-date the medieval ruins on the Council Isle by around two or three thousand years. Someone on Islay raised a question about whether any of Islay's standing stone groups have solar alignments, as can be read in an article about the Winter Solstice. I know of several sites on Islay which have been linked to various astronomical events. These include the stone circle at Cultoon, the standing stones at Ballinaby and the standing stone at Finlaggan.
https://www.islayinfo.com/islay-cultoon-stone-circle-ballynaby-standing-stones.html