City of Gold, noun phrase
Also with small initials. Golden City.
1924 L. Cohen Reminisc. of Jhb. 31The City of Gold — more or less — does not pride itself on his matured glories.
1991 M. Mthethwa in Pace Feb. 52‘I packed my belongings and headed for the city of gold,’ recalls Elizabeth. Liza left her home in 1982 to seek fame in Johannesburg.
Also with small initials. Golden City.

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