Greece grounded all flights Jan. 4, 2026, due to a technical failure in air traffic control systems, causing widespread delays and reroutes.

Due to an unexpected technical issue that interfered with air traffic control radio frequencies, grounding aircraft and leaving passengers stranded, Greece suspended all flights nationwide. Major airports, including Eleftherios Venizelos in Athens, were affected by the outage, which stopped all arrivals and departures by 9 a.m. local time. The majority of incoming flights were rerouted to Turkey and other nearby nations. After 11 a.m., air traffic gradually resumed, but interruptions persisted into the afternoon. No injuries or safety incidents were reported, and authorities pointed to outdated equipment as a probable contributing factor. The civil aviation authority acknowledged that the incident was unprecedented, that it is being investigated, and that there is currently no timeline for a full recovery.