Aboriginal tribes inhabited the Australian mainland 42,000 years ago. They had to face a European invasion that began in 1770 when Great Britain seized the East Coast of Australia. The British built prison colonies on the mainland and transported prisoners from Europe, who were forced to do community service there. These colonies laid the foundation for federations from which the entire country was later formed. Australia is currently a federal state with a democratic system. It suffers from a lack of precipitation, so it is the driest continent on earth. Most cities like Sydney, Melbourne, Brisbane, Perth, and Adelaide are concentrated on the country’s coast. Fauna and flora have developed separately on other continents, so most local species are endemic. The world’s largest massif is Mount Augustus in Western Australia, competing for the title with the famous Uluru. Australia also includes the largest barrier reef, which is more than 2000 kilometres long.