Experience the power and might of the Southern Ocean here, and notice the map of Tasmania that is formed at the seaward entrance to the cave. You’ll find this geological oddity just down the road from Port Arthur. It’s aptly named – it really is remarkable! This sea cave is actually more of a tunnel. In fact, it’s really two tunnels through the sea cliffs that join together. Visit at low tide for the best views. Climb down the steep stairs to have a look.