In Australia, there are more than twice as many kangaroos (over 50 million) as there are people.

Bob Hawke is known for being the Prime Minister of Australia between 1983 and 1991. However, his first claim to fame was holding the Guinness World Record for beer drinking between 1955 and 1957, for drinking 2½ pints of beer in 11 seconds. (source)

On the morning of New Year's Day, 1963, Dr. Gilbert Stanley Bogle, one of Australia's top physicists, and his girlfriend Margaret Chandler were found dead in suburban Sidney, Australia, near Fuller's Bridge, on the Lane Cove River. The best efforts of the Sydney police, Interpol, and the FBI notwithstanding, no-one has been able to figure out who killed them, how they were killed, or why they were killed. This case is unique in that all three of these questions are unanswered. (source)

The Dingo is the only wild, carnivorous animal that is native to Australia.

In 1967, the Prime Minister of Australia, Harold Holt, disappeared, never to be found again.

The lowest mountain in the world is Mount Wycheproof in Victoria, Australia, with a summit just 140 feet above the surrounding plains.

The original boomerangs, used by Australian aboriginals, did not return. They were used for hunting, where returning would be disadvantageous. (source)

Three pairs of common English rabbits were let loose in Australia in the middle of the nineteenth century. Within a decade, the six rabbits had multiplied into millions, menacing the country's agriculture.

The longest train ever was a BHP Iron Ore train of 682 ore cars that travelled 447 miles (719 kilometres) from the company's mines to Port Hedland, Western Australia on June 21, 2001. The train was 7.53 kilometres (4.57 miles) long and required eight locomotives—two at the front, another two after the first 168 cars, another two after 168 more cars, another locomotive after 168 more cars, and another at the end of the train. Prior to that, the longest train was a Norfolk & Western train of 500 coal cars that travelled 253 kilometres between Iaeger, West Virginia, U.S.A and Portsmouth, Ohio, on November 15^th, 1967. It weighed 42,000 tonnes and was 6.5 kilometres long. (source)

On December 1, 1948, a man was found, dead, on Somerton Beach, Australia. Police were unable to identify the man, who carried no identification or passport, just cigarettes, tickets, gum, a comb, and, most interestingly, a scrap of paper with the words tamam shud, Persian for "it is finished," printed on it. It was determined that this was the final page of The Rubaiyat of Omar Khayyam. Following a police appeal for the book, a man turned the book in, saying that he had found it on the front seat of his unlocked car around the time of the murder. On the inside back cover of the book were a jumble of letters; police assumed the writing to be some sort of code, but cryptologists were unable to break the code. Furthermore, a coroner's inquest was unable to determine a cause of death, although some sort of poison was suspected. To this day, the identity of the man, the cause of death, and the meaning of the code are all unknown.