In 1860–61, Robert O'Hara Burke and William John Wills led an expedition of 19 men with the intention of crossing Australia from Melbourne in the south to the Gulf of Carpentaria in the north, a distance of around 3,250 kilometres (approximately 2,000 miles). At that time most of the inland of Australia had not been explored by non-indigenous people and was completely unknown to the European settlers.
The south-north leg was successfully completed (except that they were stopped by swampland 5 kilometres (3.1 mi) from the northern coastline), but owing to poor leadership and bad luck, both of the expedition's leaders died on the return journey. Altogether, seven men lost their lives, and only one man, John King, crossed the continent with the expedition and returned alive to Melbourne.
Gold was discovered in Victoria in 1851 and the subsequent gold rush led to a huge influx of migrants, with the local population increasing from 29,000 in 1851 to 139,916 in 1861 (Sydney had 93,686 at the time). The colony became fantastically wealthy and Melbourne grew rapidly to become Australia's largest city and the second largest city of the British Empire. The boom lasted forty years and ushered in the era known as "marvellous Melbourne". The influx of educated gold seekers from England, Ireland and Germany led to rapid growth of schools, churches, learned societies, libraries and art galleries. The University of Melbourne was founded in 1855 and the State Library of Victoria in 1856. The Philosophical Institute of Victoria was founded in 1854 and became the Royal Society of Victoria after receiving a Royal Charter in 1859.