Today we booked a trip to El Teniente mine and its accompanying town, Sewell. You can only do this with a tour. We were picked up on the outskirts of town, and joined about 20 other people heading up into the Andes. Near Coya we entered the El Teniente compound and were surprised to know Sewell was another 36 km.
The scale of the mine beggars belief. Over 17,000 people work there and the investment in infrastructure was obvious. Whereas in parts of Chile, even the main road, the Ruta 5, is little more than a dirt track, here the roads were properly metalled to a high standard.
As you approached the mining area, the mountains were strangely denuded of any forestation or geological features. They had been opencasted. The depth was amazing but we couldn't capture the scale. Seemingly only the mine at Chiquimata is deeper.
At one point the bus stopped and everyone disembarked. Before our eyes were a flock of condor swooping on the thermals. This is the fifth time we have been to south America and we have never seen condors before. Their black and white markings are do distinctive. It was an honour to see them.
Carrying on, we reached Sewell. The air was thinner and we both felt a little light-headed. There was no English spoken so we grasped bits of what the guide said. Sewell is one of five UNESCO sites in Chile: Humberstone, Chiloe, Valparaiso, Sewell and Rapa Nui (Easter Island), We have been lucky enough to see four, and funnily enough discussed visiting Rapa Nui yesterday.

http://whc.unesco.org/en/list/1214/gall ery/

The mining town is perched precariously on a mountain slope. Thousands of people used to live here when Rancagua was a day's journey away by train (now 90 mins by bus).
The buildings were brightly coloured and, unusual for Chile, multi-storied, some with lifts. Only a small proportion of the original buildings are left, and most were locked up. Some were dormitories for unmarried men and women. Others were family flats with shared facilities.
There was a strict system of social segregation here with the mainly white North Americans as the A class, skilled workers B class and then everyone else C class.
In this microcosm of the outside world, the town was complete with shops, a cinema, sports club and bowling alley but no pubs. Only the A class were allowed to drink but there was a culture of bootlegging.
The main staircase was the place to meet and be seen as there were few open spaces in this vertical town.
Over about 30 years the town was depopulated and the last inhabitants left in 1981 to live in and around Rangagua.
Nearby you could see huge lorries heading into tunnels leading deep underground.
On the way back the tour stopped for a late lunch at the Campo de Coya (sweetcorn, lettuce, beetroot and rice.) We sat with a family whose father was from Chile but now living in New Mexico. His wife refused to let him drive in Chile so they were doing their holiday on public transport.
Back at the hotel we were both tired so ate in the restaurant.