The prince and the Duchess of Cornwall, along with Belgium's Princess Astrid, will tour Hougoumont farm, which has recently undergone a £3m project to restore it, following years of neglect. It will be officially opened on Wednesday. The new memorial shows two life-size soldiers struggling to close the north gates of the farm, to save it from being overrun by the French. This defence of the farm was so important that Wellington later said the outcome of Waterloo "turned on the closing of the gates at Hougoumont". On one of the stone gates are carved words from the Duke's official despatch after the battle: "The army, on any occasion, never conducted itself better." On Thursday there will be a national service at St Paul's Cathedral to commemorate the anniversary. The prince and duchess will attend, as will the Earl of Wessex, the Duke of Wellington, senior members of the armed forces and descendants of those who fought at Waterloo.