Let’s begin, first of all, by becoming aware of the location of the Iron Belt where our grandparents fought – and perhaps even left their lives. After the formation of the Basque Government, the Iron Belt was built in 1936 to prevent the Francoists from taking over Bilbao, among other things, they wanted to protect the port. Thus, from Punta Lucero in Muskiz, through the Triano Mountains, from Sudup to Arrigorraga, from Monte Upo to Egirlas and from Harvard to Gaztelumendi, this defense system that ended in Fika, explains Alfredo Irusta.

The obvious betrayals

Colonel Alberto de Montaud y Nogerol directed the design of the Iron Belt and the details of the works. Under his command were Pablo Murga and Alejandro Goikoetxea. Murga was surprised to give the enemy the plans of the fence and was shot on November 19, 1936. The chief engineer, Alejandro Goikoetxea, also passed to the Franco side and, he did, in February 1937, delegated all the plans of the Belt to the Franco command. Thanks to these betrayals, the work of the nationals was greatly facilitated.

The defence system consisted of five sectors. The first is from Punta Lucero in Zierbena to Sudup; the second is Mount Ganekogorta, from Ugao to Sudup; the third is from Massif Upo, from Ugao to Usansolo; the fourth is from Usansolo to Gaztelumendi and the last is from Gaztelumendi to the sea. It also had two resistance centres in Sudup and Ugao.

The main reason for the rupture of the Iron Belt, apart from the betrayals, was the difference between the sides. At the beginning of the war there were eight in the artillery against one, and in the planes the difference was total: The Popular Front had almost no apparatus. It can be said that the Francoists would break the Iron Belt in the same way, both finished and unfinished.

The construction of the Iron Belt was modelled on the French defence system after the First World War: The Maginot Line. The belt was well consolidated on both roads and roads, such as Arrigorraga, Egirleta, Harvún, Mungia and Urduliz, but other places were not sufficiently consolidated due to lack of time. And other fronts, such as from Ondarro to the valley of Mena, had to be preserved. After all, it was more than a hundred kilometers to protect. It took a lot of time and people to take care of it. Alfredo Irusta adds, “The women did a great job in the construction of the Iron Belt, as did the young men. They received food and wages for working, so it became a source of income for many. In addition, those who did not go to war also worked together with several detainees in the prison.”

The route

We reached Harvur, where we saw a part of the Iron Belt that remains at the intersection of the road. It's a wall, protected from the top. Between two farms there is a support wall, which is also part of the Belt. On the other hand, a wall of the current sawmill is a spectacular vestige of the Belt of the time. Then take the road to Morga, pass the Goikolexea and on the left we will go to Gaztelumendi, a well-defined road.

In Gaztelumendi, we arrive at the same place where the Iron Belt was broken after the Franco attacks. Two nests of machine guns are complete, and it can be seen that another is missing the upper part. These nests are fortresses with visors or sheds, where the Republican warriors installed automatic machines that controlled the angles of firing from it. In this mountainous area, the remains of trenches can be easily seen.

Monuments of triumph of the Francoists

In Gaztelumendi there is a monument in honor of the dead on the Franco side. The Nationals used about 160 cannons to break the Iron Belt from this point. In places where they fought hard, they erected monuments like the ones you can see in the pictures above. These are found, for example, in Sabigaín, Lemoa and Orduña.

We left Gaztelumendi and headed for Gangu, Galdakao, with movements similar to those of the Francoists. They took Santa Marina and then headed from Santo Domingo to Artxanda. Here there is also a nest of machine guns and a memorial cross made by the nationals. This monument, in the column that supports the cross, has three dates engraved: two of the Carlist Wars and the Spanish Civil War.

The machine-gun nest of Artxanda, on the other hand, is unique in this area, with a view of the town of Derio and not well cared for, since it is surrounded by weeds.

14,000 employees

The Iron Belt was very well built in terms of roads and roads; its communications were very well reinforced to be able to receive ammunition on time. Many people participated in the construction. Thirteen architects, twelve industrial engineers, two mining engineers, an agricultural engineer, three surveyors, sixteen contractors and the most important, worked for 14,000 workers to build the wall that would make Bilbao inaccessible.

Mountains full of footprints

The remains of this great work, as well as those of the dead in it, are many around us and can be found everywhere where the war was fought. In addition to what we have seen during the walk, the Trinchera can be found in most of the mountains of Bizkaia: In Gaztelumendi, Kutxizen, Unben, Barrika, Punta Lucero, Monte Montaño de Muskiz... The latter are those made on the trenches built during the Second Carlist War. From Galdames to Sudup there are also traces of a strong defensive line, and in Amurrio, Elgetan and Markina, among others, you can see traces of machine gun nests. When we go to the mountains of these areas, it is not a difficult task to be cautious and remember what our ancestors lived. Without a doubt, the Iron Belt is a unique example of the ups and downs of the war that took place in the Basque Country.