The Magna Carta was sealed at Runnymede, a meadow by the River Thames in Surrey, England, on 15 June 1215. This location is the traditional site associated with the sealing of the charter after a meeting between King John and the group of barons led by the Archbishop of Canterbury, Stephen Langton. The event occurred during a negotiation that sought to limit the king’s rights and protect certain liberties for the nobility and, more broadly, for subjects under feudal law.

If you’d like, I can provide more context about why Runnymede was chosen, how the sealing ceremony was carried out, and how subsequent copies and attestations of Magna Carta circulated.