The geological formation is technically referred to as an 'anticline' where sedimentary layers have been tilted almost 90 degrees.
The village of Finestres was abandoned due to the isolation caused by the construction of the Canelles dam and the subsequent flooding of lower access routes.
The rock walls reach heights of up to 20 meters in certain sections.
The site is located within the Montsec mountain range, a region known for its high concentrations of limestone cliffs and fossil sites.
The hermitages found within the walls, such as San Vicente, indicate that the location held strategic religious and defensive significance during the Middle Ages.
The Muralla de Finestres consists of two parallel vertical limestone ridges created by geological folding, forming a natural defensive barrier around the abandoned medieval village of Finestres. These distinct rock formations, known as the 'Great Wall of the Montsec,' flank a valley that was partially submerged following the construction of the Canelles Reservoir. The site features the remains of the Hermitage of San Vicente, which sits perched on one of the crags overlooking the water. Visitors can access the area via hiking trails that traverse the remnants of the village, which was largely depopulated in the mid-20th century. The geological formations were created during the Alpine orogeny, resulting in layers of rock being pushed into a near-vertical orientation.
From the trail leading toward the Hermitage of San Vicente, looking back at the gap between the two parallel limestone walls.
Wear sturdy hiking boots with aggressive tread, as the terrain is steep, loose, and uneven.
Carry significantly more water than you expect to need, as there are no natural water sources or shops in the immediate vicinity of the walls.
Check the water levels of the Canelles reservoir before arriving, as high water levels can restrict access to certain lower trail sections.
Attempting to visit during midday in summer, when the lack of shade and high temperatures create dangerous hiking conditions.
Practice leave-no-trace principles; do not disturb the ruins of the abandoned village or climb on the fragile rock formations.
