It is described by many as the most important document in British history and one that has influenced the legal framework of other countries for centuries – the Magna Carta, or Great Charter.
Today only four of the original 800-year-old copies survive and on Monday (February 2) they were united for the very first time at the British Library in London.
Magna Carta was agreed between King John and rebellious barons in June 1215. The handwritten document drawn up in a field near Windsor Castle protects life, liberty and property and states that no-one, not even a monarch, is above the law.
It is as important today as it was back in medieval times.
"Its meaning has evolved over time and it's come to be a symbol for all sorts of individual liberties and freedoms and rights, so its symbolic value has really increased hugely over time," said Clare Breay, Head of Medieval Manuscripts at the British Library.
Magna Carta is the foundation for America's Bill of Rights and has influenced other English-speaking countries around the world.
"There is a key clause right in the middle which is more of a statement of principle and that has had an enduring legacy really. That clause established the right to a free trial and prevented the king from arbitrarily arresting or imprisoning people and that clause is very, very flexible and that is at the heart of the document and that is what people really look back to," said Breay.
Normally just two of the Magna Cartas live at the British Library, with the others residing at Lincoln and Salisbury Cathedrals. There were originally 13 drawn up and sent around the country, but just four survived.
Only the Lincoln copy goes on international tours.
The 800th anniversary this summer is an opportunity to spark debate about what Magna Carta means around the world today and how it is still relevant.
It took five years in the planning to get the four Magna Cartas in the same room and on public display. They will be at the British Library for three days, then spend Thursday in parliament before being split up again and going on tour to celebrate the 800th anniversary of the signing this June.
More than 40,000 people applied for the just 1,215 slots to view the four Magna Cartas united.