The main seat of the British monarchy, Buckingham palace in London, is where most of the real work is done by the Sovereign, who is still head of state of 16 monarchies, represented in each country by a different, usually local Governor-general -who occasionally all meet with the Monarch at the palace- and (informal) leader of the Commonwealth (also including most other former British colonies, mainly republics). The palace staff of several hundred takes care of the large complex, with over 600 rooms which are all still used, plus sizable gardens; both are stretched especially at the occasion of a formal state visit by a foreign monarch or president. When the core staff follows the Sovereign on summer holiday at the Scottish Balmoral castle, a large part of Buckingham palace is opened for visits to the public, generating a significant contribution to the expense for its maintenance, including the invaluable royal art, archive and other collections.
—KGF Vissers