This year is the 150th anniversary of London's Tube. [...] Beck, who died in 1974 aged 72, worked out that people did not need to know the true distance between stops.

The plaque will be unveiled by London Transport Museum director Sam Mullins who said: “Beck's map was revolutionary in its simplicity. It has become a London icon and influenced the design of many Metro maps across the globe, as well as being the inspiration for many contemporary artists and designers.”. “Harry Beck: the Man Who Drew London”, Rachel Smethers,

And yet when Beck first presented his ‘diagram' to Underground management, they were unsure. Lines running horizontally, vertically or at 45-degree angles were plotted on a grid. Eschewing geography, it looked like a cross between an electric circuit diagram and a Mondrian painting. While it was no longer possible to tell the distance or precise geographic location of stations at a glance, Beck reasoned that this was unimportant. [...]

In 1933, with a spirit of modernisation in the air, the time was right to see how the public would respond to Beck's radical ‘diagram'. After a test run of 500 copies were distributed from a few select stations in 1932, 700,000 copies of the map were printed in 1933. It proved an instant success.