The County of Duras was a medieval county with its seat at the castle of Duras. The 18th century version of this castle still stands and is a part of modern Sint-Truiden in the province of Belgian Limburg. The county was one of several counties in the Hesbaye region (Haspengouw in Dutch) which covers parts of several Flemish and Wallonian Provinces of Belgium. As a distinct entity under the name Duras the county only existed within the 12th century. After the first male line of counts died out, the county of Duras came by marriage to the Counts of Montaigu, whose other holdings were further south. Duras itself became part of the neighbouring County of Loon, which was at that time ruled by cousins of the original counts of Duras.
The history of Duras is entangled with that of its powerful neighbour, Sint-Truiden Abbey. The first certain counts of Duras were under-advocates (subadvocati) of the abbey, who were responsible for exercising the secular aspects of lordship on their worldly estate, such as death penalties and military matters. As in many similar cases in the twelfth century, this office became powerful and controversial. There was conflict not only between the subadvocatus and the abbey's own brethren and tenants, but also with the higher advocatus, the Dukes of Limburg, and their successors the Dukes of Brabant. Such conflicts are a major theme in the medieval Gesta or chronicle of the abbey.