The Cidacos River is a

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage ...

of the

Ebro , name_etymology = , image = Zaragoza shel.JPG , image_size = , image_caption = The Ebro River in Zaragoza , map = SpainEbroBasin.png , map_size = , map_caption = The Ebro ...

. Its source is Los Campos, in

Soria Soria () is a municipality and a Spanish city, located on the Douro river in the east of the autonomous community of Castile and León and capital of the province of Soria. Its population is 38,881 (INE, 2017), 43.7% of the provincial population. ...

, and it flows for 77 km (48 mi) until its reaches the Ebro at

Calahorra Calahorra [] ( an, Calagorra, la, Calagurris) is a municipality in the comarca of Rioja Baja, near the border with Navarre on the right bank of the Ebro. During Ancient Rome, Ancient Roman times, Calahorra was a municipium known as ''Calagurris ...

(

La Rioja La Rioja () is an autonomous community and province in Spain, in the north of the Iberian Peninsula. Its capital is Logroño. Other cities and towns in the province include Calahorra, Arnedo, Alfaro, Haro, Santo Domingo de la Calzada, and N� ...

). It flows through or past various towns like Villar del Río, Yanguas, Enciso, Peroblasco,

Arnedillo Arnedillo is a village in the province and autonomous community of La Rioja, Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin) ...

, Santa Eulalia Somera, and Bajera,

Herce Herce is a town and municipality in La Rioja province in northern Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: " ...

Arnedo Arnedo is the third largest town in La Rioja, Spain. It is located near Calahorra, and has a population of about 15,000 people. Its economy is based on the shoe industry. History The area of Arnedo has been inhabited as early as the Neolithic ...

, Quel,

Autol Autol is a village in the province and autonomous community of La Rioja, Spain. River Cidacos The Cidacos River is a tributary of the Ebro. Its source is Los Campos, in Soria, and it flows for 77 km (48 mi) until its reaches the Eb ...

, and

. The river is used for

irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...

purposes and is often dried up near Calahorra.

See also