We can say that the origin of the walkways of Alquézar that we know today is closely tied to the hydroelectric plant that began construction in 1909 and was completed in 1913.

HISTORY
Availability and use of the vero river water
It is true that the waters of the Vero River and the narrowness of its channel have been used for various purposes for a long time, both basic (supply of drinking water, fishing, and irrigation) and various engineering works (mills, fulling mills, and the Alquézar hydroelectric plant). This is demonstrated by the different structures that can be found along the channel. As specified in the municipal ordinance, the route is subject to the following prohibitions:
Features and route
The river, flowing from North to South, enters the Sierra and Cañones de Guara Natural Park at the height of Sarsa de Surta and exits it through Alquézar. In its first kilometers, the Vero and its tributaries form impressive limestone canyons, which are some of the most representative karst phenomena in the park.
The Vero River flows underground in its upper part until it re-emerges at Lecina. From there, at the Lecina spring, it carves its way through spectacular canyons and narrow gorges. The cave paintings near Lecina and Alquézar bear witness to the ancient activity that emerged in this environment during prehistoric times.
Historical fluvial heritage
In Islamic times, the Vero acted as a natural communication route between Al-Qsar (Alquezar, the fortress) and the Muslim city of Barbastro, the district capital of Barbitanya. Later, the river would become the natural corridor for the penetration of the Aragonese troops as they advanced from Sobrarbe towards the conquest of the flatlands.
Centenary conviction of the value of this natural space
The first vision (of which there is a record) of prosperous activity by the inhabitants of the area dedicated to serving tourists was already predicted by the French writer, photographer, and explorer Lucien Briet at the beginning of the 20th century:
``If we move from the geological point of view to picturesque aspects, I dare say that the gorges of the Vero River, which are part of the curiosities and wonders of the Pyrenees, will gain their full value when the Upper Aragon is crisscrossed by roads and railways and becomes accessible to everyone.
Currently, if it were possible to traverse from one end to the other—from Lecina to Alquézar—these gorges without straying too far from the watercourse, one could undertake a journey unique in its kind. And for this, a simple bridle path and a few walkways placed at very specific points and narrowings would suffice! Places like the Lecina gorge, the labyrinth of the Oscuros, the strait of the Clusas, the bridge of Villa Cantal, or the crack of the Fuente ravine, publicized in posters and reproduced in guides, would enjoy worldwide reputation.
With certainty, thanks to progress—and to the great benefit of the poor farmers who inhabit it—the day will come when the Upper Aragon plays a glorious role in the theater of nature; it will inevitably be something that happens, something I would not dare to doubt for a single moment; but unfortunately, it seems that by the time that blessed day arrives, the one who first discovered and immortalized the gorges of the Vero River with his photographs and writings will have long disappeared.``
In the footsteps of Lucien Briet, Sublime Pyrenees
And indeed, as he predicted, this happened long after his disappearance, although he will always be remembered as the pioneer of the dissemination of the natural and cultural heritage of our territory.
Favorable orography for hydroelectric generation
At that moment, no one else considered walkways intended to show visitors the wonders hidden in these gorges. However, progress was on the horizon, as was greater utilization of energy resources in the industrial context.
``On April 11, 1908, authorization was requested to divert 99 liters per second from the Vero river within the municipal term of Alquézar, intended for industrial uses.
In 1909, the project was approved and work began on August 1st, as this was the month when the river carried the least amount of water, thus facilitating construction. The dam was heightened with cement work and the canal we see today was built to carry water to the turbines of a mini hydroelectric power plant installed in an old mill. To reach the machine house, a 44m tunnel had to be excavated. Interestingly, no dynamite costs are recorded in the project, suggesting that the tunnel was dug purely by pick and shovel. The cost of the work totaled about 7,400 pesetas, with the tunnel accounting for no less than 60% of the construction cost. A drainage canal was also built towards the river.
The drop to the turbine is 18m.
But things did not end there. The 99 l/s barely provided enough power for Alquézar, and considering the needs of other towns, an increase to 600 l/s was requested.
In September 1912, the new request was approved. The dam was enlarged to a height of 5 meters.``
Reminiscences of Alquézar, Miguel Carravedo Fantova.
A different perspective on the Vero
Regarding the construction of the walkways, it is known that the first one to be built was the one that connects the water inlet from the weir to the path, although the first one that existed (of which only some remains are left, right under the beginning of the trail) came very close to the riverbank. This construction was followed by the stretch that connects the trail, right after the landslide, to the central power plant (still visible along its entire path a few centimeters below the current one), and both were built years later by those in charge of the plant.
Its construction was intended to facilitate access from the plant to the water inlet for cleaning debris that constantly clogged the inlet, thereby reducing the efficiency of the turbine.
The birth of a new adventure sport
In the late 1980s, a new form of sporting activity began to develop in the area, previously only practiced by a few locals from Huesca and its surroundings, as well as French mountaineers. This activity is canyoning.
This is when the change happened.
Numerous families from Alquézar had to emigrate due to a lack of resources, and the town was in advanced decay. However, at this time groups—increasingly numerous—of French people eager for adventure began to arrive. Many began to bring the first neoprene suits and to stay several days in the town and its surroundings to enjoy the wonderful natural environment offered by the hidden valleys deep in the Sierra de Guara.
Plans began for the restoration of the existing old concrete walkways:
``With the significant boom in adventure sports in the Sierra de Guara, the Vero river descent stands out. Upon reaching Alquézar, at the old hydroelectric plant now out of use, there are two old sections of walkway anchored in the rock, over the river, which are used to traverse parts of it that are not walkable. These sections were built for the plant's use. They are now used by hikers, and their condition is greatly deteriorated.``
Project for the replacement of walkways over the Vero river in Alquézar (Huesca); June 13, 1995