Mount Barker in SA has an awesome yearly Scottish fest, also a big yearly weekend fest for steam driven machinery; there used to be a big German beerfest in Hahndorf which has now been moved to Adelaide, also yearly; a big Cornish-culture festival, the Lowender Kernewek, including the Cornish Gorsedd, up in the Copper Towns every two years; and also in that area, around Kapunda, a big Celtic music festival every year. And of course the English Ale, a pagan festival with lots of Morris dancing and a huge torchlit parade with Giants and guisers and a big Druid gathering most years in late May. Several of these events which involve me are in May, so that's why I tend to drop off the edge a bit each May -I'm way busy!
Adelaide and environs also have a lot of arts, music, literary and drama festivals, and the folk festivals every few years, but I rarely get to those.