Sewell

Sewell is a mining town on the Andean slopes of central Chile, more than 2,000 m up and about 60 km east of Rancagua. In 1905 the Chilean government authorised the American mining engineer William Braden to work the El Teniente copper mine. The Braden Copper Company built roads, a concentrator and a railway to Rancagua, and raised this town for the workers of what became the world's largest underground copper mine. It was named after the company's first president, Barton Sewell.

The ground was too steep for wheeled vehicles, so the town was laid out around a great central staircase rising from the railway station, and it became known as the City of Stairs. Its timber buildings were painted green, yellow, red and blue. On 8 August 1944 an avalanche killed 102 people, and in June 1945 smoke from a fire outside spread through the mine and killed 355 workers.

American companies owned the mine and the town until the copper industry was nationalised in 1971. From the late 1960s, when the state became the main shareholder, workers were moved down to Rancagua and buildings were demolished. Policy later turned to protection, and Sewell was declared a National Monument in 1998. It was inscribed in 2006.