Blenheim Palace (/ˈblɛnɪm/ BLEN-im[1]) is a country house in Woodstock, Oxfordshire, England. It is the seat of the Dukes of Marlborough and the only non-royal, non-episcopal country house in England to hold the title of palace. The palace, one of England's largest houses, was built between 1705 and 1722, and designated a UNESCO World Heritage Site in 1987.