Sewell is a Chilean mining town that is not currently lived in. It is located on the slopes of the Andes in the commune of Machalí, Cachapoal Province, Libertador General Bernardo O'Higgins Region, at an altitude between 2,000 and 2,250 meters. In 2006, it was named a UNESCO World Heritage Site. The town was once a company town built by Braden Copper Company to provide homes for workers and their families who worked at El Teniente, the largest underground copper mine in the world.

In 1960, about 16,000 people lived in Sewell. After the government took control of the mine, and especially after copper mining was nationalized in 1971, the government moved workers to the valley. The government built the Copper Highway to help workers travel to the mine and related jobs. Some buildings were torn down in the 1980s, but others were fixed up for workers hired for specific jobs and restored to protect the town’s history. In 1998, the Chilean government declared Sewell a National Monument.

History

The town of Sewell was founded in 1906 by the Braden Copper Company as a company town to help extract copper from the El Teniente mine. It was named after Barton Sewell, the company's first president.

During the Great Depression, the Braden Copper Company became part of Kennecott Copper Company. In 1917, the foundry or smelter was moved from Sewell to Caletones, where a new town developed around it.

At first, male workers in Sewell lived in shared housing called colectivos. Later, homes for families were added. Playgrounds, plazas, shops, and a movie theater were built over time. People walked up and down vertical staircases to reach different parts of the town. Streets ran horizontally and were unpaved because of heavy snow in winter. There were no cars. On the west side of Cerro Negro, a camp for foreign workers was built.

Ore was transported down the mountainside to Graneros, where it was loaded onto railway cars. A narrow gauge railway connected Sewell to the nearby town of Rancagua, 32 kilometers (20 miles) away. The railway was built in 1906 and completed in 1911. The total length was 72 kilometers (45 miles), with an elevation change of 1,500 meters (5,000 feet).

By 1915, Sewell had a hospital, fire department, and social club. Buildings and homes were made of wood and painted bright colors like yellow, red, and blue. At its peak in 1960, Sewell had more than 16,000 people. By 1918, the town had over 12,000 residents.

Sewell is known as the "City of Staircases" because it was built on steep terrain where wheeled vehicles could not travel. The town was built around a large central staircase, called the Escalara Central, starting from the railway station. All supplies came into the city via the narrow gauge railroad. Pueblo Hundido had living quarters, while below, El Establecimiento contained the concentrator, hydroelectric plant, and tramway.

On August 8, 1944, 102 people died in an avalanche when slopes above the town collapsed. Other dangers included earthquakes, avalanches, and mine explosions.

In June 1945, 355 workers died and 747 were injured in the El Teniente mine due to carbon monoxide poisoning. Smoke from a fire outside the mine spread inside, an event known locally as the "Smoke Tragedy." This disaster led the government to create new safety rules.

In 1967, Kennecott Copper Corporation gave up sole ownership of the site when the Chilean government bought a 51% share. At this time, many people moved from Sewell to Rancagua. The government built the Copper Highway to help workers commute to the mine.

In 1971, the mine was nationalized by the Allende government. In 1977, CODELCO (Chile's national copper company) began moving families out of Sewell into the valley. The company town had been active for over 70 years and supported the world's largest underground mine. CODELCO started demolishing buildings in the town.

Many people wanted Sewell preserved because of its importance in Chilean history and its unique location in the Andes. Demolition stopped in the late 1980s. In 1998, the Chilean government declared Sewell a National Monument. In 1999, Chile's College of Architects named Sewell one of the country's 10 most important urban works. Nine books have been written about life in Sewell. In 2006, UNESCO designated Sewell a World Heritage Site after Chile's nomination.

During the 1980s, some buildings were remodeled to house thousands of contract workers at the mine, but they were later moved out. Other buildings have been restored to keep the town's original look. About 50 restored buildings remain, and a history museum is located in one of them.

CODELCO uses some buildings for offices. Today, only the basic facilities needed for mining remain in Sewell. The area is not accessible by private vehicles. The government allows visitors only through tour operators from Santiago and Rancagua.

Climate

Sewell has a warm-summer Mediterranean climate, called Csb in the Köppen climate system. This means that at least four months of the year have average temperatures above 10°C (50°F). The summers are dry and not too hot, while the winters are cold and wet, sometimes with snow.