Costa de' Nobili is located on a hill surrounded by the sandy and clayey lands of the depressions of the Po and Olona rivers. In the early 13th century, Costa became the property of the Pietra family of Pavia. The castle complex, dating back to the 13th-14th centuries, consists of two buildings (one of which is the ancient Palace, now housing the Town Hall) connected by a central tower. On either side were two additional towers, now truncated. The central tower, 20 meters tall but reduced to a ruin, stood over the old entrance to the castle.

On State Road No. 234, which leads from Pavia to Cremona, about 20 km from Pavia, a junction leads to Costa de’ Nobili, a small town in the Pavia area situated on some rises of sandy and clayey land that the Po and Olona rivers have deposited over millennia. In recent decades, many of these elevations have been leveled as they were used as sand quarries for road construction, flood defense embankments for the two rivers, and as building materials.

As noted by Don Gianfranco Mascheroni in his book "Costa de’ Nobili Pietra and the Church of S. Maria Assunta" (Pavia, 1982), it was the Lombard kings, particularly Liutprand (8th century), who encouraged settlement in these wild and marshy lands, prone to frequent floods, linking them, through donations, to the Benedictine monasteries of Santa Cristina and Salvatore in Pavia. Among these lands was the location of Costa, originally named for its elevated position compared to the surrounding area.