Híjar River

River in northern Spain

The Híjar river or The Híjar is a river in northern Spain whose waters give rise to the Ebro River. This was accredited as early as 1862 by Pedro Antonio de Mesa in the first known hydrogeographic survey. This river runs more than 20 km from the headwaters of the Campoo Valley, and then part of its flow filters and makes a short subway journey of 800 m, resurfacing along with 4 other springs in the town of Fontibre, then receiving the name of "Ebro". The flow of the Hijar River that is not submerged continues along the surface in an easterly direction and joins the Ebro at Reinosa, a few kilometers downstream. This fact was scientifically demonstrated by technicians from the Geological and Mining Institute of Spain in 1987, after pouring fluorescein into the river, and observing that the same flow filtered by the Híjar was the one that came out dyed in the Fontibre spring.

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