There is one wall by the epic Christmas Tree in the atrium and the rest are scattered around on level one, near the cinema.
It’s free to visit the walls and take some fun shots and they are open all the time.
It’s a good idea to visit the Crown Christmas Show while you’re there too. The show runs on the half hour daily from 10am to midnight. It happens where the giant baubles are in the atrium.
All of the Christmas fun is fully accessible. Crown is a short walk from Flinders Street Station and there are trams stopping out front. There is also a car park for those who prefer their own wheels.