To save the pilot whales stranded on Tasmania's West Coast, rescuers have to navigate Hells Gates

To save the survivors of Tasmania's largest recorded mass whale stranding, rescuers need to navigate the animals out of Macquarie Harbour — but that's no easy feat. Chief among the significant hurdles facing the rescuers is the topography and geography of the harbour itself, and a tricky passageway known as Hells Gates. But as Tasmanian Parks and Wildlife regional manager Nic Deka explained, a different tidal system exists within Macquarie Harbour, which, at 315 square kilometres, is more than six times bigger than Sydney Harbour. The name Hells Gates was coined by convicts passing through on their way to the Macquarie Harbour Penal Station on Sarah Island. The journey through Hells Gates is tricky Hells Gates is the name of the dangerously shallow entrance to Macquarie Harbour, and it's what the surviving whales have to be guided through to get to the Indian Ocean.