The Jamison Valley forms part of the Coxs River canyon system in the Blue Mountains of New South Wales, Australia. It is situated approximately 100 kilometres west of Sydney, capital of New South Wales, and a few kilometres south of Katoomba, the main town in the Blue Mountains.
The traditional inhabitants of the land in what is now known as the Jamison Valley are the Aboriginal Gundungurra people who are estimated to have lived in the region for 40,000 years, stretching south towards the Burragorang Valley, north of Goulburn.
The Jamison Valley was named by Governor Lachlan Macquarie in honour of Sir John Jamison (1776-1844), a prominent landowner and physician who visited the Blue Mountains with the governor in 1815.
Later, as local towns were beginning to develop, the British naturalist Charles Darwin toured the area. He stayed at the Weatherboard Inn in Wentworth Falls in 1836, and undertook a walk along Jamison Creek to the escarpment of the Jamison Valley, where he was suitably impressed by the spectacular views. His route is now commemorated as Darwin's Walk, starting in Wilson Park, Wentworth Falls, and following Jamison Creek to the escarpment.
Coal mining in the valley was started around 1872 by John Britty North, with large-scale infrastructure (Katoomba Scenic Railway) used to overcome the terrain.
The Jamison Valley stretches north-south from just outside Katoomba to the Mount Solitary ridge; in this direction it is approximately 4 kilometres (2.5 mi) long. From west to east, it stretches from Narrow Neck Plateau to Kings Tableland, making it approximately 10 kilometres (6.2 mi) wide. Like the entire Sydney and Blue Mountains region, the valley is a sandstone area, characterised by steep sandstone cliffs. Deeper into the soil there is a layer of shale, which is softer than the sandstone. As this layer of shale was eroded by the watercourses, it collapsed and brought the sandstone down with it, creating the characteristic sandstone valleys and canyons of the Blue Mountains, of which the Jamison Valley is one.