This upcoming sunday (August 9) will be the 45th installment of The City to Surf fun run. What began with just 2 000 participants in 1971, has grown into one of the great fun runs of the world with around 75 000 now taking part each year. While the route has been the same, the start line originally was at the Sydney Town Hall with runners running the full length of Park Street. The photo below shows the sea of runners making their way down Park Street. In those days, one could still park their car on the street on the day of the race and if you needed to cross Park Street, tough luck. You had to wait for all runners to run.
Source: Anonmyous. 1971. "Here to Stay". The Sun, September 6, 3.