The castle dates back to the mid-10th century, when the viscount of Barcelona, Guitard, issued a letter of settlement in which he entrusted the local peasant farmers themselves with building the castle. It occupies a small hill at the bottom of the Anoia valley.
The most visible element of the castle is the cylindrical tower, which stands at about six metres tall. Other elements were later added to this original construction, including the Romanesque church of Sant Nicolau, other rooms (of which some walls can be appreciated) and some walls that have been partially preserved on the southern and eastern sides of the hill.
Originally belonging to the viscounts of Barcelona, at some point in the mid-12th century it was donated to the house of canons of Santa Maria de Solsona. The castellans (the Freixe family) were involved in a long, drawn-out legal battle with the house of canons over payment of the proportion of taxes due to the family. This was no minor matter since the municipal district of Freixe contained significant forest resources, mills and agricultural land suitable for the construction of an irrigation channel.
The letter of settlement of Freixe, which dates from 955 AD, was the first to be issued in the area now encompassed by the county of Anoia. It shows how, just a few decades after the conquest, the new borderlands were gradually repopulated starting from the Pyrenees.