Whitehall Palace

The Palace of Whitehall (or Palace of White Hall) was the main residence of the English monarchs in London from 1530 until 1698 when all except Inigo Jones's 1622 Banqueting House was destroyed by fire. Before the fire it had grown to be the largest palace in Europe, with over 1,500 rooms, overtaking the Vatican and Versailles. The palace gives its name, Whitehall, to the road on which many of the current administrative buildings of the UK government are situated, and hence metonymically to the central government itself.

Further information on the Wikipedia page