Castillitos Battery is located in Tiñoso cape, it was built for the purpose of defending Cartagena city and its bay, 25km away.
Cartagena has been one of the main military ports of Spain, located at the end of a natural bay that protects the city. Along the siecles, many military constructions were made in order to defend this bay, first ones very close to the city, but when the scope of cannon shots was growing along the time new batteries and fortifications were needed further off the main arsenal, each time at a higher distance.
In this case, Castillitos battery is the last example of such approach. It was built between 1933 and 1936 made by two Vickers guns, model 381/45 mm (15 inches), that were able to reach 35km with a cannonball of near 1 ton. Beside another battery called Cenizas battery, locate near 60 km away, allowed to cover the natural bay of Cartagena crossing their fires.
Indeed, only one time it was used in a conflict, at the beginning of Spanish Civil War, when it fired one shot against a Nationalist squadron of three ships, that was enough to discourage their attack.
It was decommissioned and abandoned in 1994, later restored in 2010.
By the way, its name means "little castle", it comes from its architecture that was designed as a medieval castle. Beside this battery there were built a upper one called Atalayón and a lower one called Jorel (another three Vickers guns remained) both to help the main one.
About Cartagena city. It was founded by the carthaginian Hasdrubal, using the same name as the original city of Carthage. During the Roman Empire, it was called Carthago Nova. This place has been one of the most important ports of the western Mediterranean Sea, and it is a confluence of civilizations. A city not known as a touristic place, but that it's worth to have a look at it.