double height of the state rooms on the piano nobile; however, not even a blind window, such as those often seen in Palladio's own work, is permitted to alleviate the severity of the facade. On the ground floor, the rusticated walls are pierced by small windows more reminiscent of a prison than a grand house. One architectural commentator, Nigel Nicolson, has described the house as appearing as functional as a Prussian riding school. The principal, or South façade, is 344 feet (104.9 m) in length (from each of the flanking wings to the other), its austerity relieved on the piano nobile level only by a great six-columned portico. Each end of the central block is terminated by a slight projection, containing a Venetian window surmounted by a single storey square tower and capped roof, similar to those employed by Inigo Jones at Wilton House nearly a century earlier. A near identical portico was designed by Inigo Jones and Isaac de Caus for the Palladian front at Wilton, but this was never executed. The flanking wings contain service and secondary rooms—the family wing to the south-west; the guest wing to the north-west; the chapel wing to the south-east; and the kitchen wing to the north-east. Each wing's external appearance is identical: three bays, each separated from the other by a narrow recess in the elevation. Each bay is surmounted by an unadorned pediment. The composition of stone, recesses, varying pediments and chimneys of the four blocks is almost reminiscent of the English Baroque style in favour ten years earlier, employed at Seaton Delaval Hall by Sir John Vanbrugh. One of these wings, as at the later Kedleston Hall, was a self-contained country house to accommodate the family when the state rooms and central block were not in use. The one storey porch at the main north entrance was designed in the 1850s by Samuel Sanders Teulon, although stylistically it is indistinguishable from the 18th-century building. Interior Inside the house, the Palladian form reaches a height and grandeur seldom seen in any other house in England. It has, in fact, been described as "The finest Palladian interior in England." The grandeur of the interior is obtained with an absence of excessive ornament, and reflects Kent's career-long taste for "the eloquence of a plain surface". Work on the interiors ran from 1739 to 1773. The first habitable rooms were in the family wing