And yet the world’s most famous arches may well be those – with no claim to high culture, innovative engineering or grand historical narrative – of McDonald’s. Under the sign of these arches, currently on display at more than 30,000 restaurants in 119 countries, 68 million customers a day are served variations on a theme of burgers and fries washed down with Coke and shakes. But this famous M logo formed of two intersecting golden arches and developed over a number of years came about more by accident than design.

In 1937, Patrick McDonald, who had come to California from New Hampshire the previous decade, opened The Airdrome, an octagonal drive-up hot dog stand outside Monrovia airport, northeast of Los Angeles. He ran it with sons Richard (‘Dick’) and Maurice (‘Mac’) who, in 1940, moved the stand to San Bernardino. Eight years later the brothers re-launched it with their new assembly line fast-food concept, meaning they could sell burgers at 15 cents, half the price of their competitors. A new roof sign boasted “McDonald’s Famous Hamburgers”.