There were huge rises in house prices across virtually every county in the UK over the past decade, according to new figures, with Northern Ireland particularly dominant. All but one county in Britain has seen house price inflation of at least 150 per cent since 1997, Halifax's figures revealed, with over two out of five of them even recording a trebling in property prices. The highest growth of all was recorded in County Armagh, with a 331 per cent rise over the past ten years and Northern Ireland also accounted for another four of the top ten performing counties in the UK, with Cornwall seeing the greatest price rises in England. Meanwhile, Surrey, which was the most expensive county in the UK in 1997, remains so now with an average house price of £364,115, while County Down is the only area outside the south of England to feature among the UK's ten costliest counties.