Ancient city, northeast of Lisbon, on the north shore of the Tapajos River in Portugal.
Populated since at least the eighth century BC, the town was known to the Romans as Scallabis and was an important administrative center of their Lusitania province. Under the Arabs it experienced a military and artistic fluorescence, becoming a center for poets and bards. Although made to swear allegiance to Alfonso in 1095, it was not definitively reconquered by Don Alfonso Henriques until 1147.
When King Don Sancho came against his brother, to besiege him in Santarem.