The fortress was located at the meeting-point of the Oudenburg-Aardenburg Roman road (the Zandstraat) and the Reie canal.

Count Arnulf I of Flanders (889-965) extended the Bruges fortress to create a powerful, imperial administrative centre of one and a half hectares.

The castle church—which was dedicated to Our Lady and Saint Donatian—was built to the north, within the fortifications, and a chapter of canons was later established.

[2][3] The demolition of the cathedral doubled the size of the square to around 1.1 hectares, making it even larger than the Markt.

[4] Some of the foundations of Saint Donatian’s Cathedral, which was demolished in 1799, can still be seen in the cellars of the Crowne Plaza Hotel.