RN20 Highway to Andorra Closed Indefinitely After Major Rockfall

France's RN20 highway, the primary route from Ax-les-Thermes to Andorra, remains closed in both directions with no reopening expected during the coming week after a major rockfall near Mérens-les-Vals exposed a highly fragile slope. The shutdown affects the section from Ax-les-Thermes' southern roundabout to L'Hospitalet-près-l’Andorre, following initial assessments that revealed greater instability than anticipated.

The rockfall occurred around 2:30-3:30am on the night of 30-31 January 2026 at kilometre 86.5, near the former cable car site. Large boulders smashed the road surface, causing severe damage. Ariège Subprefect Émilie Baromes described the event as "exceptional" during a Saturday briefing, noting its unusual scale. Sunday's brief weather window allowed helicopter flyovers, confirming the overlying slope as "very fragile and unstable." Purge operations and detailed studies are set for Monday or Tuesday, weather permitting, before DIRSO can begin stabilization, debris removal, and repairs—work expected to extend well beyond next week.

Ongoing bad weather has blocked drone and further aerial inspections essential for safety. Emergency access remains restricted to critical cases only. Ariège Prefect Hervé Brabant heads a crisis cell involving gendarmerie, DIRSO, the departmental council, RTM, emergency services, SNCF, and Andorran officials, addressing impacts on healthcare, mobility, home care, school transport, and businesses. Rail links from L'Hospitalet to Toulouse operate with slight delays and extra services coordinated with SNCF and Occitanie Region. Supplies reach isolated areas like Mérens-les-Vals via secondary paths.

Andorra's Foreign Affairs Minister Imma Tor confirmed France notified Andorra around 4am via established protocols. The government and Encamp parish offered COEX equipment, personnel, and emergency support to Occitanie for slope stabilization, road repairs, and aid to cut-off communities. Tor highlighted this severe winter's repeated access issues but praised swift cooperation that averted casualties, warning a daytime incident "could have been catastrophic." Experts are investigating possible climate influences, including ground thawing.

The detour—for cars and winter-equipped buses, excluding trucks over 19 tonnes—routes from RN20 exit 6 near Pamiers via RD119 to Mirepoix, RD625 to Lavelanet, RD117 through Belesta and Quillan, RD118 to Mont-Louis, RD66 (former RN116) to Bourg-Madame (La Guinguette d'Ix), then RN20 to Porte-Puymorens. Signage appears from A61 and A66. Authorities urge avoiding non-essential travel, mountain shortcuts, or inadequate winter gear like snow chains alone, amid reports of risky driving.

Andorra maintains yellow alerts for snow—pausing midday in central and southern parishes before resuming—and winds, with level 3 avalanche risk. Restrictions continue on CG2 from Tarter, CG3 from Serrat, CG4 from Pal, and CG5 from Erts. Pas de la Casa businesses report heavy strain in a tough season. Monitor official updates.