| Castro Urdiales | |
| Settlement Type: | Municipality |
| Pushpin Map: | Spain#Spain Cantabria |
| Pushpin Map Caption: | Location in Spain |
| Subdivision Type: | Country |
| Subdivision Name: |  Spain |
| Subdivision Type1: | Autonomous community |
| Subdivision Type2: | Province |
| Subdivision Name2: | Cantabria |
| Subdivision Type3: | Comarca |
| Subdivision Name3: | Eastern coast of Cantabria |
| Coordinates: | 43.3844°N -3.215°W |
| Elevation M: | 19 |
| Area Total Km2: | 96.72 |
| Established Title: | Founded |
| Established Date: | Flaviobriga 74 AD |
| Population Demonym: | Castreños |
| Population Density Km2: | auto |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Postal Code Type: | Postal code |
| Postal Code: | 39700 |
| Area Code Type: | Dialing code |
| Leader Title: | Alcalde |
| Leader Name: | Susana Herrán Martín (2019) |
| Leader Party: | PSOE |
Castro Urdiales (pronounced as /es/) is a seaport of northern Spain, in the autonomous community of Cantabria, situated on the Bay of Biscay. Castro Urdiales is a modern town, although its castle and the Gothic-style parish church of Santa María de la Asunción, date from the Middle Ages. Its chief industries are tourism, fishing, and oil-packing of fish, especially sardines and anchovies. The Lolin and La Castreña anchovy canning factories serve as a reminder of the town's closeness to this industry and its proximity to the sea.
Although the number of people registered in the town is around 32,000, the summer population can double or even triple this figure. The town is popular because of its beaches and scenic harbor.
Castro Urdiales was originally called Portus Amanum, and was the chief city of the Autrigones. In AD 74 a Roman colony was established under the name Flaviobriga, during the reign of emperor Vespasian. It was most likely established to mine the abundant iron in the area.[1]
In 1163 the town of Castro Urdiales received its municipal charter.[2] It lay at the western tip of the coastline of Navarre until 1200, when the kingdom was invaded by Alfonso VIII of Castile.[3] [4] Castro Urdiales benefited much from its location at a crossroads in the trade between northern Europe and Castile. It remained in Biscay until 1476 at least, but it is not cited in the seigneury's assemblies thereafter.[5] Until the 18th century, the town recurrently attempted a reincorporation to Biscay (attested in 1799), but its attempts were met with the frontal refusal of Bilbao on account that it could tip the scale against its own trade balance.[6]
It was destroyed by the French in 1813, but was speedily rebuilt and fortified. Its rapid rise in population and prosperity dates from the increased development of iron mining and railway communication which took place after 1879.
The monument complex of Castro Urdiales, also known as Puebla Vieja, has medieval origins and is located near the sea. It was declared a Conjunto histórico in 1978.
The Church of Santa María de la Asunción is in Gothic style. Built under the protection of King Alfonso VIII of Castile in the 13th century (though it was finished in the 15th century), it is a basilica church with three naves. In the interior are the images of the White Virgin and the Reclining Christ, and three Gothic carvings of the Magi. It was declared a National Monument in 1931.
The Castle of Santa Ana is located near the port and the church of Santa María de la Asunción. In modern times it housed a lighthouse.
Other sights include:
