Full image caption
In the 1960s and 70s the Mount Pleasant Sorting Office in Clerkenwell was thought to be the largest in the world covering an area of 7.5 acres. To ensure that mail could be sorted efficiently and effectively a system of Post codes was introduced across the country. Trials in Norwich in 1957 were successful and by 1974 the entire country had been coded. The first fully automatic sorting machines were not introduced until 1979 and until this date sorting had to be completed by hand. This photograph was taken by Grant when accompanying a visit to the sorting office by the National Association of Youth Clubs.
© Henry Grant Collection/Museum of London