Which railway carries Spain’s AVE trains through the 28.4-kilometre Guadarrama Tunnel?

The Madrid–Valladolid high-speed rail line carries AVE trains through the 28.4-kilometre Guadarrama Tunnel.

The Guadarrama Tunnel is a twin-bore railway tunnel through Spain’s Sierra de Guadarrama. Its two parallel tubes allow trains to travel in opposite directions while meeting modern high-speed safety and ventilation requirements.

The tunnel forms a crucial part of the route north from Madrid toward Valladolid and onward toward northern Spain. It opened with the Madrid–Valladolid high-speed line in 2007, significantly reducing journey times across the mountain barrier.

It is easy to associate the tunnel with Spain’s better-known Madrid–Seville or Madrid–Barcelona corridors, but it belongs to the northern route. The line uses Spain’s standard high-speed gauge rather than the broader Iberian gauge used by much of the older conventional network.