The binomial of mines and railways has generated some of the densest and most complex railway networks in our country. Asturias, the Almería coast, Linares, and Huelva are regions where, just a few years ago, the creaking of wagons and the agonizing puff of steam locomotives were an inseparable part of the landscape. In this context, the railway responsible for this greenway between the Andévalo of Huelva and the Spanish-Portuguese border, set along the navigable stretch of the Guadiana River, emerges. This region, with its rich mineral wealth, had a copper and sulfur deposit area near the village of El Sardón, exploited by the company 'The Bede Metal.'

The main market for this production was outside our peninsula, and the best route for shipment through these lands was the Guadiana River itself, which has about 50 km of navigable stretch in its final section. The most suitable point for mining shipments from the Las Herrerías Mines, as this mining site was called, was a sharp bend in the river, which came to be called Puerto de La Laja. A powerful loading dock and a small mining and railway village were created here. The railway began operating in 1890, but in its early years, it did not reach this site.

The first transports involved an aerial section between the railway and the nautical route. No, nothing was transported by airplanes: it was a simple mining cable from the Sardón terminal to the river dock. However, the disruption of the loading cycle increased the shipping costs, the most idle part of the business, so between 1905 and 1914, work was done to eliminate the aerial part. The original 20 km were extended with a downhill section to the port and, on the opposite side, to Puebla de Guzmán. In total, 32 kilometers of track were created, generating small mining villages along its banks. Mining and railways experienced significant expansion, but the lack of depth at the La Laja dock for ships led to the abandonment of this intermodal traffic. It was 1965, and all train and boat traffic shifted to trucks and roads. The mines were closed a few years later, and only the path, now a greenway, remains of the railway.