First transmitted in 1957, Sir Mortimer Wheeler describes the results of his excavations of the 4,000 year-old, red brick Indus Valley civilization city of Mohenjo-daro in modern-day Pakistan.
Image caption, These seals with writing on were found in the city of Mohenjo-Daro. What do you think they say? What can we learn about the writing that was left behind? Well, not very much.