Battle of Kosturino

The Battle of Kosturino was a World War I battle fought between 6 and 12 December 1915. It was fought in the initial stage of the Macedonian campaign, in the Balkans Theatre. On 6 December, Bulgarian troops attacked the French and British-held trenches in Kosturino, at the time part of the Kingdom of Serbia (present-day North Macedonia). Though the early offensive was held in check, on 8 December, Bulgaria managed to infiltrate the Memesli ravine. Bulgaria then seized Crete Simonet, thus threatening to outflank the Allies. The Entente defeat at Kosturino led to the complete withdrawal of Allied forces from Serbia, thus enabling the Central Powers to build the Berlin to Constantinople rail line. In the meantime, the Allies concentrated on solidifying their defenses in Greece.