The dolerite columns along Bruny Island's south-eastern shore were forged roughly 180 million years ago, when magma forced its way into sandstone as Gondwana began to split apart. Erosion did the rest. What remains is a coastline of vertical organ-pipe cliffs, blowholes and sea caves that no road reaches and no walking track properly reveals. It can only be read from the water, which is why the bruny island wilderness coast eco cruise with lunch exists in the form it does. Bruny is really two islands, north and south, joined by a narrow isthmus called The Neck. The Nuenonne people of the Lunawanna-Alonnah country lived here for millennia; the island's two southern townships still carry those names. European charts arrived late and repeatedly. Abel Tasman sheltered off this coast in 1642. Tobias Furneaux followed in 1773, James Cook in 1777, William Bligh in 1788 and 1792, and Bruni d'Entrecasteaux in 1793, who gave the island the name that stuck. Adventure Bay, the departure point, is named for Furneaux's ship. The bay's wide crescent of white sand made it one of the most-visited anchorages in the southern hemisphere during the whaling era. The waters offshore matter as much as the rock. The cruise route runs south towards Fluted Cape and the Tasman Sea, crossing nutrient-rich upwellings that support Australian fur seal colonies, migrating humpback and southern right whales, short-tailed shearwaters, white-bellied sea eagles and, with luck, pods of common and bottlenose dolphins. The Friars, a scatter of exposed rocks near the island's southern tip, hold one of Tasmania's larger seal haul-outs. Much of the coastline sits within South Bruny National Park, and the marine environment is managed with the sort of restraint that keeps a place worth visiting. That restraint shapes the vessels. Purpose-built open-sided boats, low-slung and highly manoeuvrable, are designed to enter sea caves and pass beneath waterfalls rather than observe them from a distance. It is a form of access that larger craft cannot offer and that has made bruny island wilderness coast eco cruise with lunch tours a fixture of Tasmania's south for more than two decades. The visitor centre at 1005 Adventure Bay Road, open 09:00–16:00 daily, functions as both check-in point and interpretive space, with free entry to the centre itself and tour fees applying to the cruise. What distinguishes this stretch of coast from other Tasmanian wilderness cruise routes is scale compression. Australia's highest sea cliffs, deep-water caves, a national park, an active seal colony and a working island community of oyster farms, cheese makers and berry growers occupy a landmass of barely 362 square kilometres. Few places offer so much geological and ecological range within a single afternoon on the water.