This aerial photo was taken by Milton Kent, a pioneer of aerial photography. It shows the city before work had started on the Sydney Harbour Bridge. In the foreground you can see Princes Street running next to the Sydney Observatory — this street was demolished to make way for the bridge. Kent took his photos with a half-plate oblique aero camera he imported in 1920 from Carl Zeiss AG in Germany. He continued to photograph Sydney from the air right through to his retirement in 1961.