over 100 feet (30 metres) wide. Anciently the Dukes of Norfolk also had a townhouse, more properly a ducal palace, in the City of Norwich, the capital of the County of Norfolk, which was greatly enlarged by Thomas Howard, 4th Duke of Norfolk (d.1572), whose London townhouse was then the London Charterhouse just outside of the northern wall of the City of London, re-named "Howard House". England London In the Middle Ages, the London residences of the nobility were generally situated within the walls or boundary of the City of London, often known as "Inns", as the French equivalents are termed hôtel. For example, Lincoln's Inn was the town house of the Earl of Lincoln, and Gray's Inn of the Baron Grey de Wilton. At that time the Tower of London, within the City, was still in use as a royal palace. They gradually spread onto the Strand, the main ceremonial thoroughfare from the City to the Palace of Westminster, where parliamentary and court business were transacted. Areas such as Kensington and Hampstead were countryside hamlets outside London until the 19th century, so mansions in these areas, such as Holland House, cannot be considered as true historical townhouses. Bishops also had London residences, generally termed palaces, listed below. The greatest residence on the Strand was the Savoy Palace, residence of John of Gaunt, Duke of Lancaster, the richest man in the kingdom in his age and the father of King Henry IV. His chief seat was Bolingbroke Castle in Lincolnshire. The Strand had the advantage of frontage to the River Thames, which gave the nobles their own private landing places, as had the royal palaces of Whitehall and Westminster and further out from the City Greenwich and Hampton Court. The next fashion was to move still further westwards to St James's, to be near the Tudor royal court. In the 18th century, Covent Garden was developed by the Duke of Bedford on his Bedford Estate, and Mayfair by the Grosvenor family on their Grosvenor Estate. The final fashion before the modern era was for a residence on the former marsh-land of Belgravia, on the southern part of the Grosvenor Estate, developed after the establishment of Mayfair by the Duke of Westminster. Many aristocratic townhouses were demolished or ceased to be used for residential purposes after the First World War, when the scarcity and greater expense of domestic servants made living