The wildlife, caves and clean sandy beaches are just some of the attractions THE WORDS 'Australian islands' conjure visions of the Great Barrier Reef and celebrated resort islets Dunk and Hayman. But just off the coast of Adelaide, in south Australia, Kangaroo Island is making a name as the country's coolest destination. About 10,000 years ago the piece of land now known as Kangaroo Island had reached a watershed. The continent's tectonic plates were shaking their booty and the ocean was gradually eroding the land bridge between Kangaroo and the mainland. The result, 10 millennia on, is more than opportune as the island has become something of a 'lost world' - a matchless wilderness crammed with outstanding natural beauty, wildlife, pure air and clean water - all just 45 minutes by ferry from Cape Jervis, just outside Adelaide. Nothing lies between the island and the Antarctic and, after Tasmania and Melville, off the coast of Darwin, this is Australia's third-largest island at 150km long and 30km wide, with about a third taken up by conservation parks. When Europeans first arrived in Australia, they found no Aboriginals living on the island. However, archaeologists have unearthed stone implements and hazard a guess that the island's original two-legged population died out for reasons yet to be determined, at about the time Julius Caesar was eyeing a different island off the coast of Europe. Kangaroo Island's isolation means it is free from dingoes, foxes and rabbits, while the authorities have introduced koala and platypus, which are threatened elsewhere in Australia, to ensure their survival. It does not take too much guesswork to deduce how the island arrived at its name, which was bequeathed by the explorer Matthew Flinders, who lowered the marsupial population after slaughtering numerous kangaroos there in 1802. Kangaroo Island and the seas around it swarm with dolphins, sea lions, penguins, pelicans, wallabies and goannas. Apart from its fauna, the island's geology showcases some amazing land formations, with the Remarkable Rocks and Admirals Arch two of the highlights in the 33,000-hectare Flinders Chase National Park. The Kelly Hill Caves were discovered in 1881 and daily tours take in this stunning system of caverns and sinkholes. There are also full-on spelunking expeditions that delve deep into Kelly's ornate maze of calcite formations. Little Sahara, in the centre of the island, is a range of spectacular sand dunes that rise directly out of the bush. Sand boarding from the razor-back ridges is thrilling. Kangaroo Island's park rangers are masters at getting visitors up close and personal with resident penguins, which waddle their way from the waters around Kingscote and Penneshaw to cosy seaside burrows each evening. Similar tours take in colonies of sea lions as they doze in the sun after lengthy fishing forays in the Southern Ocean. Kangaroo's fresh air certainly sharpens the appetite and the island's growing range of gourmet produce - from award-winning sheep milk cheeses at the Island Pure Sheep Dairy to pure Ligurian honey and olive oil - is on the menu at several restaurants and cafes. The winter here is on the chilly side, but the summer brings locals and visitors down to the seaside. Sydney University recently evaluated 10,000 beaches across Australia - rating them on clarity of water, privacy and cleanliness - and Kangaroo Island's Vivonne Bay came out top. Vivonne Bay is just one of dozens of long, curved, sandy beaches there - perfect for beachcombing, picnics, surfing, swimming or fishing - and one of the best reasons for making a trip to this latter-day, off the beaten track Eden.