The expansion of British control over other areas of the continent began in the early 19th century, initially confined to coastal regions. A settlement was established in Van Diemen's Land (present-day Tasmania) in 1803, and it became a separate colony in 1825. In 1813, Gregory Blaxland, William Lawson and William Wentworth crossed the Blue Mountains west of Sydney, opening the interior to European settlement. The British claim was extended to the whole Australian continent in 1827 when Major Edmund Lockyer established a settlement on King George Sound (modern-day Albany). The Swan River Colony (present-day Perth) was established in 1829, evolving into the largest Australian colony by area, Western Australia. In accordance with population growth, separate colonies were carved from parts of New South Wales: South Australia in 1836, New Zealand in 1841, Victoria in 1851, and Queensland in 1859. The Northern Territory was excised from South Australia in 1911. South Australia was founded as a "free province" — it was never a penal colony. Western Australia was also founded "free" but later accepted transported convicts, the last of which arrived in 1868, decades after transportation had ceased to the other colonies. In the mid-19th century, explorers such as Burke and Wills went further inland to determine its agricultural potential and answer scientific questions.