In the Trove archive, I came across this photograph of huge crowds on the Mound, Edinburgh:
Further research established that massive crowds gathered on The Mound to watch the historic March of the Thousand Pipers. The march took place on August 18, 1951. It was organized as a centre-piece of the 1951 Festival of Britain. An estimated 500,000 spectators packed the streets of Edinburgh that day, completely overwhelming the city’s thoroughfares.
