A hundred million euros per month is a considerable sum, no matter how it is spent, but the scale of this investment becomes even more striking when considering that the entire amount is being channelled into a single railway axis in Spain. The Mediterranean corridor is currently the focus of an extensive development programme by Adif, which by May 2025 has already accounted for eight billion euros in allocated funding.
The trans-European corridor begins in Algeciras, at the southernmost point of the Iberian Peninsula, and reaches Perpignan in France. It splits into two branches: one runs inland through Madrid, and the other follows the coastline, linking all the main Spanish ports facing the Mediterranean. Spanish authorities have decided to fast-track the completion of projects along the Mediterranean corridor, showcasing how European Union resources from the Next Generation EU programme can be swiftly and effectively deployed.
Work is progressing across all areas of the Mediterranean corridor, particularly in Andalusia, where construction sites for both new sections and upgrades of existing lines stretch over 500 kilometres. The projects start with the redevelopment of the Algeciras–Antequera route, moving on to the next segment of around one hundred kilometres between Antequera and Granada, which includes the Loja bypass, and then extends to the hub of Almería, home to one of the largest commercial ports on the Mediterranean after Barcelona.
From Almería, the corridor continues with works underway on the next 200-kilometre stretch towards Murcia, including links to the ports of Cartagena and Alicante. These ports will be connected to the new European standard gauge rail network, replacing the broader Spanish gauge. Adif is also investing in the modernisation of the Castellón–Tarragona line and is finalising plans to connect Tarragona with Lleida and Zaragoza. The aim is to facilitate intermodal freight trains and to capture domestic freight traffic heading towards the Mediterranean corridor.
It comes as no surprise that Spain is decisively accelerating the conversion of rail gauge on key axes, particularly those forming part of the TEN-T European freight corridor network. In March 2025, the latest three contracts were awarded, marking another step towards the full conversion of the Mediterranean corridor to standard gauge.
Sleepers on existing and refurbished lines are being replaced with models designed to accommodate a third rail, allowing for dual gauge operation—both European standard and the wider Spanish one. At the same time, all structures, especially tunnels, are being adapted to allow intermodal trains to pass through without clearance restrictions. A recent trend in these interventions is the replacement of the existing 3 kV direct current power system with a 25 kV alternating current system, which not only lowers installation and maintenance costs but also significantly enhances performance.
Piermario Curti Sacchi
