The largest lake in Australia is Lake Eyre at over 3,700 square miles. The lake, located in the South Australia territory, is made up of salt water and is the 18th largest lake in the world.
Lake Eyre is actually two lakes connected by a small channel. It sits at the lowest point in Australia, approximately 50 feet below sea level. It has only filled to capacity three times in the past 160 years, and it has, at times, emptied completely with only salt crystals remaining. The lake, located within Lake Eyre National Park, is named for the first European to see it, Edward John Eyre.