Salisbury Cathedral, formally known as the Cathedral Church of the Blessed Virgin Mary, is an Anglican cathedral in Salisbury, England, considered one of the leading examples of Early English architecture. The main body was completed in only 38 years, from 1220 to 1258. The cathedral has the tallest church spire in the United Kingdom (123m/404 ft). Visitors can take the "Tower Tour" where the interior of the hollow spire, with its ancient wood scaffolding, can be viewed. The cathedral also has the largest cloister and the largest cathedral close in Britain (80 acres). The Cathedral contains the world's oldest working clock (from AD 1386) and has the best surviving of the four original copies of Magna Carta (all four original copies are in England). Although commonly known as Salisbury Cathedral, the official name is the Cathedral of Saint Mary. In 2008, the cathedral celebrated the 750th anniversary of its consecration in 1258. It is the Mother Church of the Diocese of Salisbury, and seat of the Bishop of Salisbury, the Rt. Revd. David Stancliffe.