Monthly Geological Pics

DECEMBER 16  - THE DAROCA MINE

After the dark medieval lethargy, the Renaissance marks the flowering of culture. There is also a resurgence of public works and among them, those of tunnels. Leonardo da Vinci conceives underground levels in his designs of cities and thinks about the possibility of drilling mountains to carry water through subterranean channels. 

The "Daroca Mine" marks the passage from Renaissance ideas to reality. The main street of this Aragonese town (Spain), backbone of the city, coincides with the bottom of a ravine, and frequent torrential storms of water flowed through the urban center, following the layout of the street and causing heavy damage. The work was conceived with the purpose of driving and diverting torrential waters towards the Jiloca River. 

Made between 1555 and 1560, it is surely the first tunnel of the Renaissance. This fact makes it one of the most important public works of the sixteenth century in Europe. 

To carry out this truly ambitious project, the council of Daroca went to the French engineer, architect and sculptor Quinto Pierres Bedel, a specialist at that time in hydraulic works and famous for having built the aqueduct of Teruel. It consists of a tunnel of about 650 m in length and 6.7 m in width, with a variable height between 7 and 8 m, that crosses the hill of San Jorge. Inside the tunnel stands a ventilation chimney that saves the pressures from the mouth of the tunnel, as well as an area reinforced with a vault built in stonework stone to avoid a stretch of weakness. To protect the city wall and direct the waters to the mouth of the Mine, a powerful wall, called "la barbacana", three hundred meters long, was built, part of which is still preserved.

In addition, this construction has other uses, as a route for cattle and as a shorter way to go to the pasture area, without having to cross the top of the hill of San Jorge. Likewise, during the Civil War, the supply of goods was made through the Mine, which was crossed by the truck convoys as a true tunnel. 

Reason for admiration, the Mine became true pride of the city and one of the most known monuments of Daroca, at the same level as the large walled enclosure or the Collegiate Church of Santa Maria. The kings of Spain used to go "to pass the Mine" when they came to visit Daroca, as Philip II did in 1585, accompanied by his whole court and with several torches to illuminate the road. The decree of 2-VII-1968 that declared Historic Artistic Complex to the city of Daroca, includes as worthy values ​​of conservation, among others, its famous Mine.