the mouth of the Hunter River—obtained his cargo of coal for Sydney from a seam outcropping in the southern headland at the lake's entrance—a headland since known as "Reid's Mistake"—and so accidentally revealed to the settlers the coastal coalfields of Lake Macquarie. Awabakal people had used the coal at Swansea Heads for over a thousand years. It was only upon his return to Sydney that Reid found that he had not travelled far enough north to have reached the Hunter River. Coal was also found during July 1801 by the expedition, led by Lieutenant-Colonel William Paterson, to the Hunter Valley inland from Newcastle. This area would later become the vast South Maitland Coalfields. The discovery of the western coalfields did not occur until after the Blue Mountains had been crossed in 1813. Coal outcrops low in the cliffs of some valleys of the Blue Mountains and on their western side near Lithgow. In fact, it is the erosion of these relatively soft coal measures that results in the sandstone cliff faces so characteristic of the Blue Mountains. William Lawson found coal near Mt York in the area later known as Hartley Vale, in 1822. Apart from local use, western coal could not be exploited until the railway from Sydney crossed the Blue Mountains in 1869, and soon after that there were mines in the area around Lithgow. That coal had been found so readily, by colonial settlers with no experience of mining and little knowledge of their new country, so soon after the first European settlement, implied that the resource was widespread and plentiful. That proved true; an immense coal resource existed in New South Wales. Coal is still being mined within the Sydney Basin more than two centuries later. Some individual mines had been worked for well over a century. Indeed, it is only the more recent increased rate of extraction—for the export market—that will see the exhaustion of commercially viable reserves that can be extracted without unacceptable environmental damage, before the middle of the 21st century. Reasons for the trade Coal for Sydney Coal was needed in Sydney to feed the production of town gas (from 1841 to 1971), as bunker coal for steamships, and as fuel for industrial and hospital heating boilers. Brickworks were a significant user of coal as a fuel. In the C19th and very early C20th, there was also some demand for coal as