What is the "Golden Triangle"?

Hi Matilda,
I think its just a name for the affluent western suburbs, mostly the suburbs on the Fremantle train line. Subiaco, Claremont, Dalkeith, Peppermint Grove, Mosman Park, Cottesloe, and Swanbourne are some

Subiaco is clearly in the GT!

It is an area between canning bridge and heathcoat reserve in applecross you can read more here <input type="https://www.perthnow.com.au/news/wa/this-suburb-the-apple-of-perths-eye-ng-260edb1588a6e9dbf449a364bfe10760?utm_campaign=share-icons&utm_source=clipboard&utm_medium=clipboard&tid=1567990463606" name="perthnow gold triangle">

https://www.perthnow.com.au/news/wa/this-suburb-the-apple-of-perths-eye-ng-260edb1588a6e9dbf449a364bfe10760