The Manchester Unity Building is one of the architectural jewels of the Melbourne. While researching the broader history of this iconic landmark, I came across this amazing photo:
It seems that from the 1932 through to about 1940, the rooftop of the building (Level 12) was home to a Japanese garden and cafe.
The same spot today:
The structure on the right houses a suite of offices, which had been converted from apartments (built in the 1990s).
Sadly, the rooftop is no longer open to the public, although Melbourne Open House often runs tours that include it. The rooftop is currently used for private functions, by the building's tenants.