Battle of Katasyrtai

The Battle of Katasyrtai was a significant engagement between Bulgarians and Byzantines, fought in August 917 immediately after the Battle of Achelous, in a small village near Constantinople. At this time, both sides were preparing for decisive action. The Byzantines attempted to form an anti-Bulgarian coalition, but their efforts failed because of the swift response of the Bulgarian tsar Simeon. Nevertheless, the Byzantines assembled a large army, which was completely routed at Achelous. Following this victory, the Bulgarian troops advanced south. Having survived the Battle of Achelous, Leo Phokas reached Constantinople by sea and assembled the remaining troops there to block the Bulgarian advance towards the capital. The two armies clashed at Katasyrtai. 

The engagement took place at night, and the Byzantine army was routed once again.