The Battle or Siege of Adrianople (, , ) was fought during the First Balkan War, beginning in mid-November 1912 and ending on 26 March 1913 with the capture of Edirne (Adrianople) by the Bulgarian 2nd Army. The victorious end of the siege was considered an enormous military success because the defenses of city were carefully developed by leading German siege experts and were dubbed 'undefeatable'. The Bulgarian army, after 5 months of siege and two bold night attacks, took the Ottoman stronghold.