I visited this WHS in 2023 as a day trip from Rancagua. I reserved a spot with Fundacion Sewell and communicated with them via whatsapp to make sure I had an English guide and I opted for lunch to be included. I drove to Rancagua from Valparaiso very early in the morning to avoid the rush hour. The ride was very smooth and easy, apart from the thick morning fog in certain stretches. I parked my rental car inside the fence of Fundacion Sewell's Rancagua office and departure point and joined several other visitors (mostly Chilean) on one of the coaches heading toward the Sewell Mining Town. The English speaking group is usually much smaller than the Spanish speaking one and the tour guides are well organised and start the tours from opposite ends. Lunch is a canteen like experience, but the highlight there is not the food but the fact that you literally share the canteen table with some of the workers who still work there and most have family members who have worked there in the past. So it really is a positive experience and personally an unexpected highlight of the tour. I opted for the day tour; the night tour is geared mostly at teenagers and children with a special focus on a Halloween themed experience rather than a cultural tour.

On the coach, I stayed in the front seat with the guide, close to the driver and window, to take photos from the front tintedless window of the wonderful landscape outside (going up I would suggest staying on the right hand side of the bus). Already in Rancagua you'll see the stadium which was once placed in the Sewell Mining Town itself. Then you'll see whole convoys of blue and orange shuttles ferrying workers up and down the mountains to the mining sites and back, as well as long truckloads of copper, the main prized product of the mininig site. The highway is aptly nicknamed as the Copper Road and it was a major upgrade from the railways of the beginning of the 20th century. Thanks to it miners and their families no longer needed to live right in the heart of the mountains in order to work at El Teniente.

Right after viewing Machali in the distance, you'll pass by the Monument to the Mining Family which pays homage to the workers at El Teniente and their families. If there is one thing that characterises the families of Sewell in times gone by, it is the way in which they identify with and feel proud of their particular customs and lifestyle, including the epic nature of their work in the mine. This spirit is still very evident in the miners today as well as one the many patriotic billboards along the Copper Road. Another highlight on the way to Sewell, just before the extinct geyser and the narrow tunnel/bridge there's a high chance of spotting the majestic condor soaring in the skies. I was particularly lucky as there were around six or seven which we spotted going up and down. The driver stops a bit along the way so keep your cameras ready and your eyes peeled. I had missed on the Colca Canyon in Peru a couple of years before so I was very happy with this pleasant surprise.

Next you'll stop at he Maitenes control point which looks rather like a customs or border control point, but it is the entrance to the El Teniente division of Chile's national copper enterprise, Codelco, the world's largest copper producer. On the way back you'll stop again here; an interesting trivia is that randomly drivers (including the ones driving the tour bus) are stopped and have to undergo a series of alert tests to make sure that the drivers aren't too tired, since the never-ending hairpins and VERY narrow tunnels are quite dangerous and require the drivers to be skilled and lucid! If the driver fails, this will set you back 45 minutes each time, and he'll have to repeat it until he passes.

The landscape changes drastically from the lush green of the central valley which then gives way to the native trees so characteristic of the Andes foothills. At 4,920 feet you'll then enter the high Andean steppe, slight south of the Rio de Los Cipreses National Reserve, and then a desert-like volcanic landscape with industrial areas such as Caletones, Tranque Barahona, the Colon Concentrator where 85 % of the ore extracted from the deposit, 130,000 tonnes per day, is crushed, ground, thickened, filtered and dried, Chapa Verde, Adit 71, and finally the Sewell Mining Town some 60 kms away from Rancagua. It had snowed the night before my visit, so the white fresh snow added to the picturesque combined natural/industrial landscape. Once at Sewell, you are now at 2,200 metres (7,200 ft) above sea level (so it is advised to bring a light jacket or cardigan), on the slopes of Cerro Negro, right in the heart of the Andes mountains.

This mining town was founded in 1905 by a group of North Americans and Chileans determined to undertake the challenge of extracting copper in this remote and difficult to access place. It is the birthplace of large scale copper mining in Chile. A constant threat for this mining town are avalanches and/or mudslides. You'll notice a series of secondary metal staircases strangely coming out of the upper windows at the level of the roofs for this reason - avoiding getting snowed in! The main buildings you'll visit during the tour are the Teniente Club (toilet facilities here and at the canteen), Edificio Camarote 35, Edificio 42, Edificio 105, the Palitroque (Bowling) and Swimming Pool, the Church modelled on the Chiloe churches, the playground area with the small cinema, and the main square with the School which now houses the Musuem of Copper Mining. Opposite the entrance is the UNESCO WHS inscription plaque (sometimes hidden by the vendors selling copper jewellery).

The museum is very informative with lots of original stuff from the mining town (similar to some of the furniture in the buildings you visit during the tour). There's also a lift simulation with an informative video on the mining town's past, present and future; now heavily dependent on remotely controlled robots and high-tech. I really liked the room with scale models of the individual buildings showing the several layers used in constructing/restoring the non-cement buildings. At the Teniente Club you'll notice from one of the old photos on the wall that all the buildings weren't painted in the past, so the overall appearance was less colourful and much more like the mining town of Rammelsberg, Germany.

I'm usually not a huge fan of industrial WHS but this one I really enjoyed and the tour is fairly priced and really informative and well organised overall. They need to invest in a paypal account in the future to accept online payments without any expensive bank charges for bank transfers. However, I communicated my details via whatsapp and they allowed me to pay by credit card at their office in Rancagua before the tour started.