The heritage complex of Locks 25-26-27, built between 1759 and 1804, is located in the municipality of Grijota (Palencia), at kilometer marker 87.129 of the Canal de Castilla, right at the start of the Southern Branch. It is one of the canal’s most unique sections, as it brings together three consecutive locks in a single location, designed to overcome a significant total difference in elevation of 11.35 meters, along with a wide range of associated road, residential, and industrial infrastructure. Its overall function was to regulate the passage of vessels, control the flow, and harness the water’s head, making it a true hydraulic and territorial hub.
The main feature consists of three interconnected, triple-type, oval-shaped locks, constructed of limestone ashlar. Each lock has slightly different dimensions, adapted to the difference in elevation, and the structure is notable for the functional continuity between them. At the end of the right wing of the upper intake begins the intake channel, designed to harness the drop, a diversion that rejoins the canal downstream of the bridge. The excellent state of preservation and the integrity of the original hydraulic works justify its comprehensive protection and underscore its value as one of the first major achievements of the Southern Branch.
Associated with the locks are numerous complementary elements that complete the understanding of the complex: the bridge supported on the lower gates of lock 27, with a semicircular arch and limestone masonry, which ensures road continuity; the lock keeper’s house, with two floors, with ashlar plinth and brick walls, now unused but well preserved; several warehouses linked to the dock, some in fair condition and others in ruins, which reflect the intense logistical activity of the place; a small building located at the fork of the Campos and Sur branches, intended to house the canal’s management boat; a block of houses with courtyards and stables, still in use; and a mill with a flour factory, built on the foundations of an old mill and enlarged over time, evidence of the industrial use of hydraulic power.
A visit to Locks 25-26-27 offers a particularly comprehensive experience for understanding the Canal de Castilla as a living and complex system. The succession of locks, the diverse buildings, and the open landscape of Tierra de Campos allow visitors to leisurely explore a place where engineering, work, transport, and daily life were integrated in an exemplary way, making this site one of the most representative landmarks of the canal’s hydraulic heritage.
