Castell de Calders is a medieval castle in the Moianès region of Barcelona province, with documented origins dating to 956. The site was granted to Countess Ermessendis, widow of Count Ramon Borrell, eventually becoming the ancestral seat of the Calders lineage beginning in the 11th century. Most of the surviving structure dates from the 12th and 13th centuries, with later modifications in the 14th century, after which the castle experienced progressive decline. Today, fragmented ruins remain, most notably a round tower supported by modern reinforcement due to foundation instability. These remains preserve medieval feudal architecture and demonstrate the castle's historical importance to Catalan aristocratic families.
