Australia is the smallest continent but the 6th largest country. It has a population of around 20 million concentrated along the east and south east coast. The capital is Canberra. Australia was first inhabited by Aboriginal people over 50,000 years ago and was later colonized by Europeans in the 18th century. Australia has a mostly arid continental climate with hot days and cool nights. The interior outback desert covers much of the country and is too dry for many people. Famous places include the Great Barrier Reef, Sydney Harbor Bridge, and Uluru.