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Heritage of Mercury

Heritage of Mercury
Photo provided by Ian Cade
The “Heritage of Mercury. Almadén and Idrija” consists of the two largest mercury mining sites in the world. They produced the metal over a lengthy period, the Slovenian Idrijia often serving as a back-up for Almadén in Spain. Mining stopped here in the late 20th – early 21st century.

Mercury was used on a large scale from mid-16th til 19th century by the Spanish in the New World in the process of extraction of silver. It is a relatively rare metal, and dangerous to handle.

The inscribed area also includes the town centres of Almadén and Idrija. There related buildings such as a Mining Acadaemy (Alamadén) and miners’ theatre (Idrija) can be found.

Year Decision Comments
2012 Inscribed Reasons for inscription
2010DeferredAs The Mercury and Silver Binomial on the Intercontinental Camino Real. Almadén, Idrija and San Luis Potosí (Mexico)


Jorge Sanchez (Spain):
I enjoyed the visit to the mercury mines of Almaden like a child.
I paid the entry fee (13 euro) and joined a small group of tourists. We were given helmets to protect our heads, just in case, and followed the guide. We all were Spaniards, so the explanation was in Spanish language, although the guides could also speak French and English.
We took the lift and descended 50 meters. There were more floors, until over 700 meters depth.
During two hours we walked along corridors and tunnels with stops for explanation in front of the old machines used to extract the cinnabar, the ore of mercury, or quicksilver.
The quicksilver from Almaden helped to extract the silver in the Spanish colonies in America during the colonial times.
After the mines we boarded a train, then a minibus. We saw museums and games for children. All was very didactic, very attractive, even for adult people.
Apart from those mines, Almaden has a hexagonal arena and a hospital unique in the world, where the workers of the Almaden mines were hospitalized when they became sick for mercury poisoning. In some periods of time, in the past in the Almaden mines was used slave labor.
Date posted: January 2014
john booth (New Zealand):
After catching the 08.15 bus from Ljubljana station to Idrija, I reached the Antony Mine in time to get kitted up for the 10.00 tour of the mine shafts.
The tour descended only 3 of the 15 levels, but the atmosphere was stifling all the same. Down in the tunnels there were several displays showing methods of mercury extraction over the centuries. There was also a rock face with drops of mercury oozing out of it.
Like Ian I also enjoyed a plate of Idrija zlikrofi (mushroom ravioli) after the tour.
Date posted: December 2012
Hubert Scharnagl (Austria):
I visited Idrija, the Slovenian part of the WHS, in May 2012, expecting that it would be inscribed a few weeks later. Idrija is a small town with about 6000 inhabitants, 50 km from Ljubljana on the junction of the subalpine and the karst areas. The town lies in a picturesque valley surrounded by forest, quite unusual for a mining town. Mercury was mined for 500 years and until its closure Idrija was the second largest mercury mine, Almadén being the first. The WHS consists of seven parts: the old town, two other sites in the vicinity of the town centre, and four water barriers located in the surrounding mountains.
The historic mine, the Anthony's Shaft dating from 1500, is situated in the old town and is open to visitors. The guided tour takes 1.5 hours, it starts with a 20 minute multivision presentation. The oldest mine galleries are narrow and you have to bend down several times, the newer mine tunnels are wider and higher. The different steps of mercury mining and the techniques and tools that were used over the centuries are explained. And you can also see the underground chapel dating from the 18th Century. It was interesting to learn about the specifics of mercury mining. The mercury ore deposit is relatively small: 1500 m long, 600 m wide and 400 m deep, just below the town. In Idrija the metal was found both in its elemental liquid form and as cinnabar ore (mercury sulfide). However, the tour was very similar to other mining sites, nothing extraordinary.
In the old town are several buildings that are associated with mining: the entrance building to the Francis' Shaft (now a technology museum with pumps, engines and other devices), nearby a historic miner's house, the Castle Gewerkenegg (formerly the administration of the mining company, now the Municipal museum), a miner's theatre, a school building. The second part, about one km from the city centre, is the smelting plant, which needs to be reconstructed. It can only be visited from the outside.
The third part is located at the outskirts of Idrija close to the historic entrance of the Joseph's Shaft and comprises of a large water wheel (Kamšt) from 1790 and a water channel (Rake). But beware: the pump house is not regularly open, you have to ask for a guided tour at the museum. Unfortunately, we missed that. A trail leads alongside the Rake water channel through a nice forest with beeches and firs and ends after 3 km at the Kobila dam and the Wild Lake (Divje jezero). The dam and the Rake channel were used to regulate the water flow for the drive of water wheels and the transport of tree trunks that were used for supporting the mine tunnels.
The final parts of the site are four water barriers (klavže) on the Idrijca and Belca river. If you continue on the hiking trail at the Wild Lake, you would reach two of the water barriers after about 12 km. But this was a bit too far, so we decided to return and tried to go as far as possible by car. First, we drove on an asphalt road to Idrija Bela, a small village with a few houses, where you can bathe in the river. Then, after one kilometre the road became bumpy and narrow. We parked our car and went further by foot. After about 5 kilometres (moderatly uphill along the Belca) we reached the first water barrier, the Brusove klavže (photo), and after another kilometre the Putrihove klavže. These klavže are massive locks built of stone, which at a first glance appear a bit oversized for the small river. They were used to dam water and when enough water had accumulated, the locks were opened to allow the water to transport the wood downhill. The klavže are accessible, you can walk on the stone walls and go downstairs to the watercourse. I enjoyed our short hike through the beautiful forest scenery and the klavže are really impressive.
There is a lot to entertain visitors for a whole day, and Idrija offers enough for every taste: a mine, historical technical equipement, a pleasant town, a rewarding museum, and in fine weather the nice landscape contributes much to the pleasure of the visit.
Date posted: July 2012
Ian Cade (England):
“…and if I hire a car I could make it to the disused mercury mine!” little did I know that this ‘obscure’ holiday destination that I was trumpeting in the pub would prove to be such a rewarding target.

I drove to this site fresh from landing at Trieste airport, initially just assuming I would be getting in a pre-emptive tick on a site that was soon to be inscribed on the World Heritage list and little else. It actually turned out to be an exceptionally rewarding way to start my holiday in this great little corner of Europe.

Idrija is situated in a wonderfully verdant valley and the road through it was a pleasure to drive. When I arrived at the town I was suitably impressed. Rather than being the slightly utilitarian mining landscape I was expecting it was actually a rather pretty Central European renaissance town. There were lovely winding streets, trickling streams, a little white church nestled above the town and an imposing arcaded castle housing the wonderful town museum.

I arrived just too late for a tour of the mine shafts, so headed for the museum which was exceptionally well presented, and the staff were superb. They gave me an introduction to the life of the town, its heritage and its highlights. There were displays on mercury (including a bowl full of it with an iron canon ball floating atop it), mining, technology, local art, WWI, socialism and lace. Actually the Lace display proved to be very interesting, as it rounded out the life of the town, whilst the men were down the mines the women were making lace. It also prepared me for the Lace festival which had taken over the main squares and provided a great ambiance.

After soaking up the atmosphere and enjoying a plate of local speciality žlikrofi, I drove of north through the even more beautiful Soèa valley seeing the Julian alps rise around the astounding emerald blue waters.

It looks likely that Idrija will be added to the World Heritage list in 2012 alongside Almadén in Spain. I’m not really sure how much of a link there is between these two towns aside from the large mercury mines, however if Almadén is half as rewarding as Idrija, then I would thoroughly recommend a visit.

[Site 6: Experience 8]
Date posted: June 2012

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