Castle Howard by Hawksmoor. The grounds of Castle Howard are also used as part of at least two charity running races during the year. Located on the Estate, but operating separately to the house and gardens and run by an entirely independent charitable trust, is the Yorkshire Arboretum. Originally created through the enthusiasm and partnership of George Howard (Lord Howard of Henderskelfe) and James Russell, over a period of eighteen years, from 1975 to 1992, it was opened to the public for the first time in 1999 and a new Visitor Centre opened in 2006.The arboretum's extensive and important collection of 6,000
Castle Howard Treasure Houses of England group of heritage houses. Building of Castle Howard began in 1699 and took over 100 years to complete to a design by Sir John Vanbrugh for the 3rd Earl of Carlisle. The site was that of the ruined Henderskelfe Castle, which had come into the Howard family in 1566 through the marriage of Thomas, 4th Duke of Norfolk to Elizabeth Leyburne, widow of Thomas, 4th Baron Dacre. For the Duke of Norfolk's son Lord William Howard had married his step-sister Elizabeth Dacre, the daughter of the 4th Baron Dacre who brought with her the sizable estates