Retention 3

The third dam on the Campos branch of the Canal de Castilla is a heritage site of great historical and territorial interest, built between 1753 and 1757 in the municipality of Ribas de Campos, province of Palencia. Its overall function is the regulation and distribution of the canal’s water, integrating several structures that operate in a coordinated manner. The main element is a simple, oval-shaped lock, unique for having no drop or difference in level. Measuring 20 meters long, 10.10 meters wide, and 2.10 meters high, this lock supplies water to the intake located between the dam and the bridge and collects the excess flow from the Perales stream. Both the dam and the diversion channel are constructed entirely of limestone masonry and are well preserved.

Associated with it are the regulating buildings, rectangular in plan with hipped roofs, also built of limestone ashlar with stone slabs on a brick vault, which housed the water control mechanisms and the nozzles that channel the flow towards the culverts integrated into the retaining walls. The entire system retains all of its original hydraulic works and is in good general condition.

A visit to Lock 3 allows visitors to discover the complete Canal de Castilla complex, where the lock, buildings, bridge, and house form a coherent heritage unit. Integrated into a rural setting of great scenic value, it offers a serene and educational experience that helps visitors understand the technical, human, and territorial magnitude of this historic hydraulic engineering project.