In March 2025, Europe’s aviation landscape is shaped by dominant airline groups controlling key airports. Heathrow, Istanbul, Paris CDG, Schiphol, Madrid, Frankfurt, and Barcelona serve as “fortress hubs,” where IAG, Lufthansa Group, and Air France-KLM dictate capacity, routes, and fares. Turkish Airlines commands over 80% at IST, while Pegasus dominates SAW. This centralization boosts efficiency but raises competition concerns. As Europe’s airspace consolidates under a few airline giants, the balance between convenience and monopoly remains a key debate.