Two are kept in the British Library (one of which was badly damaged by fire in 1731), one in Salisbury cathedral, and one in Lincoln castle. They were all written out by different people, and while little is known about who those people were, the documents themselves provide a fascinating insight into their labours.

It sought to prevent the king from exploiting his power, and placed limits of royal authority by establishing law as a power in itself.

NEW YORK (Reuters) - A rare 710-year-old copy of the Magna Carta, among the most important historical documents ever to hit the auction block, sold for $21.3 million on Tuesday at Sotheby's.

There are clauses on the granting of taxes, towns and trade, the extent and regulation of the royal forest, debt, the Church and the restoration of peace. Only four of the 63 clauses in Magna Carta are still valid today - 1 (part), 13, 39 and 40.