The European settlement at Sydney Cove, established in 1788 after the arrival of the First Fleet, grew rapidly. By the early 19th century, the Blue Mountains had become a barrier to the expansion of the colony, which required more farming land to meet its needs, particularly after the droughts of 1812 and 1813. The local indigenous people knew at least two routes by which to cross the mountains. The first was along Bilpin Ridge, later followed by Archibald Bell with the assistance of the local Darug people (now the location of Bells Line of Road), and the second was along Coxs River. Until 1813 however, the settlers remained unaware of how to cross the mountains despite several attempts, including two by Blaxland himself. Early in 1813 Blaxland, who wanted more grazing land, obtained the approval of Governor Lachlan Macquarie and approached Lawson and Wentworth to secure their participation in a new exploratory expedition following the mountain ridges.