A major traffic disruption occurred Saturday afternoon on the E6 highway north of Oslo, Norway, due to the unexpected closure of the Nordby Tunnel. The closure, initiated earlier in the day, stemmed from a malfunction in the tunnel’s ventilation fan system, prompting authorities to shut it down for safety reasons. Despite the tunnel’s reopening around 6 PM local time, significant traffic congestion persisted in Ås, Ski, and Drøbak as drivers navigated detours. Traffic operator Annie Serup explained that the fan failure necessitated the complete closure to ensure motorist safety. The incident caused considerable delays for travelers, and residual queues remained in the vicinity of the tunnel following its restoration to service. Authorities continue to monitor traffic flow in the area.