The number of mansions, old country houses and stately homes is a marked feature in Wiltshire. Few parishes, especially in the north west of the county, are without their old manor house, usually converted into a farm, but preserving its flagged floor, stone-mullioned windows, gabled front, two-storeyed porch and oak-panelled interior. Place House, in Tisbury, and Barton Farm, at Bradford-upon-Avon, date from the 14th century. The best examples of 15th-century work are the manor houses of Norrington, in the vale of Chalk; Teffont Evias, in the vale of the River Nadder; Potterne; and Great Chalfield, near Monkton Farleigh. At South Wraxall the hall of a beautiful house of the same period is celebrated in local tradition as the spot where tobacco was first smoked in England by Sir Walter Raleigh and his host, Sir Walter Long.