The Capricorn Caves are a living laboratory displaying dramatic climate change. Evidence of these changes can be seen in stunning rock formations, their inhabitants and the fossils of creatures who did not survive. Australia has about 10,000 known caves, each unique, however these limestone caves are particularly special because of their elevation above the surrounding plains and location on the Tropic of Capricorn. Heading west- Visit the historic township of Mount Morgan. Once home to the richest and largest gold mine in the world. Fossick for 120 million year old thundereggs, or 'volcanic birthstones' at Mt Hay. Visit Blackdown Tableland National Park, a sandstone plateau rising abruptly above Central Queensland's plains. Stop in at Blackwater, the Coal Capital of Queensland and home to the International Coal Centre. Enter the Central Highlands and see Emerald's fossilised tree trunk, before exploring the Sapphire Gemfields. Heading east- Rockhampton is the gateway to the Capricorn Coast. Admire the picturesque headlands at Yeppoon and the twin peaks of Double Head, dramatic examples of ancient volcanic plugs. Take a walk to Fan Rock, an unforgettable site showing the effects of cooling on a plug; and explore the Great Barrier Reef, one of the world's seven wonders.