There are indications that Celts settled on an island formed by a bifurcation of the Reie River, already before the Romans conquered the region in 57 BC. The Romans probably built a fort on this island.

Towards the end of the first millennium the first count of Flanders had his castle at this spot. Bruges was a stronghold against the invasions of the Vikings. It was also a port because the Reie River then entered the sea not far from "Bruggia".

It is assumed that the first name of Bruges, Bruggia, originates from a fusion of "Rugja" the name of the Reie River, and of "Bryggia", the Scandinavian word for landing-place. The name Bruggia first appears on coins minted in 864.

Due to trade, mostly related to its cloth industry, the city prospered. In the 12^th century a wall was built that followed the "inner channels" which were probably dug for that purpose.

Little remains from these early days. However the site of the presumed fort and castle, became  the center of the city, the "Burg", nowadays also a major tourist attraction. The island no longer exists because part of the bifurcation of the river was filled later in history. The canals dug to protect the wall still exist for the most part, as can be seen on the map, but not the wall itself.