Following a rockfall in the Tunnel del Negrón the Autopista del Huerna (AP-66) was completely closed at kilometre 85 during the night of 22 August 2026. Traffic resumed in the morning after clearance work and technical inspections. Emergency services reported no injuries.
The Subdelegación del Gobierno en León and the Guardia Civil reported that falling material inside the structure had necessitated a complete closure. While the rock was being cleared, traffic between León and Asturias through the N-630 and his party Puerto de Pajares was diverted. The alternative route was temporarily congested but remained passable. The authorities only gradually reopened the AP-66 after a safety inspection of the affected tunnel bore.
The Tunnel del Negrón is a key bottleneck on the north–south route through the Cantabrian Mountains. The disruption comes during a period of intensive work on the road: the Ministerio de Transportes is pressing ahead with the modernisation of several tunnels and facilities on the AP-66 to renew fire safety, drainage and monitoring systems. The operator Aucalsa had already announced temporary restrictions and changing traffic arrangements in this connection. Technicians from the operator and the administration are investigating the cause of the rockfall inside the tunnel; the authorities have not yet commented on possible causes.
Politically, the incident adds to an ongoing debate. The Gobierno del Principado de Asturias has been pushing for toll relief for months while construction work and recurring incidents reduce the route’s capacity. Regional government representatives argue that closures and diversions are impairing Asturias’s economic links. The Ministerio de Transportes, by contrast, points to the need for safety and renewal work. No specific commitments on temporary discounts, compensation or penalties for the concessionaire have yet been approved.
What is clear is that the AP-66 remains the fastest route between León and Asturias; every unplanned closure diverts traffic over the weather-prone Puerto de Pajares. Following the latest clearance and reopening, the authorities and operator are closely monitoring the Tunnel del Negrón. A technical assessment of the damage will show whether additional safety work is needed in the affected section.
Editor: Mira Cadena (Article created with AI assistance).