The municipal territory of Costernino is south-west oriented over the splendid Itria Valley, known for the considerable presence of trulli, the typical local stone constructions.
Inhabited since the Upper Paleolithic, the legend says that the foundation of Cisternino was due to Sturnoi, the companion of Diomedes. After taking part in the Messapic League against Taranto, it became a Roman town and was called Sturninum. It was probably destroyed in 216 b.C. during Hannibal’s raids in Apulia.
The Basilian monks, who came from the East in the VIII century, noted the ruins of the ancient town and referred to it when they later had to localize the Greek rite abbey they had built where the Chiesa Matrice (Matrix Church) lies today, and indicated it as "San Nicolò cis-Sturninum", hence the present name of the town.