Investiture II or another member of the royal family each year. A list of those to be honoured is published twice a year, in either the New Year Honours or the Birthday Honours. Approximately 25 investitures are held annually: most in the Ballroom at Buckingham Palace, although the Waterloo Chamber in Windsor Castle and the Palace of Holyroodhouse in Edinburgh, Scotland, are also used. In 2014 The Prince of Wales held an investiture at Hillsborough Castle in Northern Ireland. Investitures are also held in other Commonwealth realms, when the Governor-General acts on behalf of the Queen. The poem "The Investiture" by
Buckingham Palace fire devastated many of its state rooms. In the year to 31 March 2017, 580,000 people visited the palace, and 154,000 visited the gallery. Her Majesty's Government is responsible for maintaining the palace in exchange for the profits made by the Crown Estate. In November 2015, the State Dining Room was closed for six months because its ceiling had become potentially dangerous. A 10-year schedule of maintenance work, including new plumbing, wiring, boilers, and radiators, and the installation of solar panels on the roof, has been estimated to cost £369 million and was approved by the prime minister in November