The Balkan States began to struggle, for the lands they took from the Ottoman Empire. Serbia and Greece declared war against Romania and Bulgaria. The Ottomans took advantige of this situation and declared war to Bulgaria, the Ottoman Army recapture historical city Edirne and advanced through the River Meric, but, the European Countries intervened and stopped the Ottomans. The Treaty of Istanbul was signed, the Turks retained Edirne and Kirklareli.