It's a bridge the majority of people in west London will have driven under hundreds of times.
Officially known as the Chalfont Viaduct, we probably woudn't give it a second look were it not for some very bold graffiti.
But emblazoned in giant letters on the side of the bridge is the unmissable message, "Give peas a chance".
Visible from the clockwise carriageway, it is just past the M40 junction and you've probably wondered what on Earth it means and why it's there.
Theories have probably run through your head as you have driven around the motorway, interrupting your Taylor Swift karaoke session, as to the intended message behind it.
They may have included any of the following:
- A PR firm for Bird's Eye trying to subliminally tell you that you fancy some garden peas for dinner
- A peace campaigner trying to share their message but with unfortunately poor spelling
- A marketing campaign behind a new version of Monopoly where all the playing pieces are vegetables
But there is actually a far simpler explanation which is revealed by a dedicated Facebook page , set up in tribute to the message.
Apparently a London-based graffiti artist whose "tag" is Peas initially daubed the word on the bridge in white paint.
Some joker then came along and added the other words, using the same colour paint and a similar font so it looks like the whole message was written at the same time.
If you look at the word "peas" you will notice the letters are slightly wider and subtly different to the other words.
Obviously the whole phrase is a play on words, referring to John Lennon's song Give Peace A Chance which got to number 2 in the charts in 1969.
It's a cracking bridge to have written it on, too. It was reportedly built at the start of the 20th century, sometime between 1902 and 1906 and is the only Edwardian brick bridge over the M25.
The main question that remains, though, is how those responsible managed to paint the words on the bridge without falling to their deaths.
Maybe they had some climbing gear, maybe their mate hung them upside down by their ankles. We may never know.