The original design for what is today Buckingham Palace, was a more modest townhouse, built in 1705 for the Duke of Buckingham. In 1761 it was bought by King George III for Queen Charlotte.
Thereafter aggrandisement of the original building began with changes in plan through two more reigns, (that of George IV, using John Nash, and that of William IV, using Edward Blore). Upon the accession of Queen Victoria in 1837, the palace became her official residence, and that of future monarchs until the present day. However, the open courtyard seen in the drawing above, with a triumphal arch, (Marble Arch), subsequently moved to the top of Park Lane, underwent further changes in 1847, because it was considered too small for a growing family and Court life.
Accordingly, a new wing, enclosing the courtyard, and forming a quadrangle was designed and built by Thomas Cubitt, as above. This became much more of the building recognised today, which was again altered in 1913, to that which we have today. It is now certainly a grand, although not necessarily pretty building, unlike its first incarnation. Fittingly it has the look of an important office building, for what George VI described as The Firm.
At the end of this week BP will again become the backdrop for a light show, as it was during the Golden Jubilee in 2002, (below).
Not quite the Great Hall of the People, but perhaps the People's Palace.
The top architectural print is from Vetruvius Britannicus c.1717-1725 and is one of several I bought from Sotheran's in Pimlico more than 20 years ago. The lower photograph shows a partial display of the collection in our predominantly black and white drawing room in the New Town, Edinburgh.
Other images are from Wikipedia, and from unknown sources.