Lake Ciconia is the largest lake of Juliana. It lies in northern Pisona Province, near the western Julian Alps.

Lake Ciconia is a glacial lake, fed by the Pretana Glacier on the slopes of Pretana, Juliana's highest mountain, which lies just across the border with Avia Province. Popular tourist town Ciconia lies on the shore of the lake. Lake Ciconia and the area surrounding it are admired for their natural beauty; the lake is a popular tourist destination, for scenic cruises, sailing and also activities like jet-skiing.