Magna Carta Island for sale on the Thames, complete with the stone tablet on which Magna Carta itself is said to have been sealed

If you could go back in time 810 years and ask those who put their seals to Magna Carta what they thought, they'd tell you it had been a waste of time and a failure. From the moment King John and his retinue rode away from Runnymede on June 15, 1215, he was already intent on ignoring everything that the 'Great Charter' had put in place. He immediately petitioned Pope Innocent III to declare it null and void, on the grounds that he'd been coerced into putting his name to the document; the Supreme Pontiff agreed, and Magna Carta was annulled just nine weeks later

Yet here we are, not far short of a millennium later, and Magna Carta isn't just remembered as a success. It's acclaimed as one of the foundation stones of democracy, and described as 'the foundation of the freedom of the individual against the arbitrary authority of the despot' by the 20th century jurist Lord Denning. The 1215 version may not have lasted long, but re-issues in 1216, 1217, and its official inclusion in the laws of England in 1297, cemented Magna Carta's central place in constitutional history.

The document was signed not in a great palace, but on the neutral ground of Runnymede, the meadows on River Thames between Windsor and Egham. Nobody knows precisely where — Magna Carta merely says 'Runnymede' — and the area has several Magna Carta-related points of interest, from memorials and monuments to the Magna Carta Tea Rooms. Perhaps the most intriguing of them all, though, is Magna Carta Island, on the north bank of the Thames, and the location of Magna Carta House — which is now up for sale at £4.5 million via Waterview.

The house itself wasn't here at the time of Magna Carta, but the island was: it was owned by Richard de Montfichet, one of the original 25 barons tasked with enforcing the document. De Montfichet's thanks for this part in history was to have his lands confiscated and to be excommunicated by the Pope, but he did get everything back a couple of years later, after pledging allegiance to the recently-installed boy king Henry III.

600 years later the island came in to the hands of a politician named George Simon Harcourt, who decided to commemorate Magna Carta by building a Norman-style house on the spot, made from irregular stone, with Welsh slate roof, cylindrical stone chimneys and various other quirks. It's was effectively part-house, part-folly — and at the centre of it Harcourt commissioned a Magna Carta Room, featuring an octagonal table inlaid with an ancient stone on which, it is said, the Magna Carta was sealed.

The house was has been updated, amended and expanded in the succeeding years, but the Magna Carta room is still just as it was. Was the stone really the one used for the document? Who knows — such claims are impossible to prove or disprove conclusively, but it's a wonderful story, and the stone table looks superb in a room decorated with the coats of arms of de Montfichet and the other 24 barons from that day in June 1215.

It's also a very beautiful home in a charming part of London's outskirts, pretty and characterful, with four acres of gardens and several hundred feet of river front which could allow you to navigate all the way into central London.

It's also a very large house indeed, with over 4,700sq ft of space, and six bedrooms, plus a two-bedroom cottage in the grounds.

As if Magna Carta wasn't enough of a claim to fame on its own, the grounds of the house hold another treasure: a tree planted by Elizabeth II when she came to this spot in 1974 on a visit with — of all people — President Richard Nixon, just a few months before he resigned in disgrace over the Watergate scandal.

The irony of Nixon visiting the site of Magna Carta just before getting his own comeuppance over the abuse of power is just another delicious little chapter in the history of this fascinating home.

Magna Carta House is for sale at £4.5 million via Waterview — see more details.