We happened to be in Sydney this year while Vivid was on. This is a festival of lights (and other things, like food). This year it runs from 26 May to 17 June 2023.
I’ve always wanted to see it, so this year we stayed an extra day in Sydney so we could.
The lights are amazing. It’s well worth seeing at least the once. Very crowded, as you’d expect, but the lights were amazing.