The closest airport to the Black Sea (at 15 min drive from it) is near Constanta city, Kogalniceanu airport. But most likely your flight will be London-Bucharest-Constanta, you don't have direct flights from London. But you do have a few low-cost companies to Bucharest, so the cost should be rather low if you book early. If I can be of any help, please let me know. Best regards, Ana Irimia
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