sentences:  High crosses may exist from the 7th century in Northumbria, which then included much of south-east Scotland, and Ireland, though Irish dates are being moved later.However the dates assigned to most of the early crosses surviving in good condition, whether at Ruthwell and Bewcastle, the Western Ossory group in Ireland, Iona or the Kildalton Cross on Islay, have all shown a tendency to converge on the period around or slightly before 800, despite the differences between the Northumbrian and Celtic types.The high cross later spread to the rest of the British Isles, including the Celtic areas of Wales, Devon, Brittany and Cornwall, where ogham inscriptions also indicate an Irish presence, and some examples can be found on Continental Europe, particularly where the style was taken by Insular missionaries.