The Chapter House is notable for its octagonal shape, slender central pillar and decorative mediæval frieze. The frieze circles the interior, just above the stalls. It shows scenes and stories from the books of Genesis and Exodus. The chapter house displays the best-preserved of the four surviving original copies of Magna Carta. This copy came to Salisbury because Elias of Dereham was present at the meeting with King John at Runnymede in 1215. He was given the task of distributing some of the original copies. Later, Elias became a Canon of Salisbury and supervised the construction of Salisbury Cathedral.