The Bay of Fires region hugs the northeastern coast of Tasmania for over 50 km so getting to the iconic region is relatively easy with driving and public transportation options available. If you're travelling from a different state in Australia you'll have to choose one of two options for the beginning leg of your journey to the Bay of Fires; flying or catching the Spirit of Tasmania (ferry service across the Bass Strait).
However, if you're travelling from somewhere else in Tasmania, driving is your quickest option. Unfortunately, there are no public transportation options available between locations such as Launceston to the Bay of Fires or Hobart to the Bay of Fires. There is a bus/shuttle service operating from Launceston to St Helens (the closest town to the Bay of Fires), however, it's pretty much impossible to get to the region itself without a car.