The San Juan Aqueduct, built between 1831 and 1836, is part of the infrastructure of the Southern Branch of the Castile Canal, designed to ensure the continuity of the canal’s route over natural watercourses. Located in the municipality of Dueñas (Palencia), at kilometer 111.620, its function is to allow the Valdesanjuán stream to pass under the canal, guaranteeing flow control and the stability of the hydraulic structure at a key point along its course.
The structure consists of a single semicircular arch, with a span of approximately 6.70 meters and a height of nearly 1.20 meters. The entire structure is about 8 meters long, 25 meters wide, and 5.50 meters high. It is built entirely of limestone masonry, a material characteristic of the canal due to its strength and durability. The design is completed with stone wing walls that channel the stream and concrete sleepers, the result of later additions that reinforce the structural integrity without altering the overall appearance of the structure.
For the visitor, the San Juan Aqueduct offers a quiet and educational stop on the canal route, ideal for observing how 19th-century engineering soberly resolved the dialogue between water, land and landscape, and for enjoying a section of the Canal de Castilla where the technique is naturally integrated into the environment.
