Thuin is located on the River Sambre (at the confluence with the River Biesmelle) in the Province of Hainaut. Its Belfry, completed in 1638 is a UNESCO World Heritage Site. The town was part of the lands of the Prince-Bishops of Liège from the ninth century onwards, and was fought over by local aristocrats and later by foreign armies and besieged many times. Most notably, the siege by the Spanish army in 1654 was lifted by the use of a huge cannon called the Spantole, a replica of which is on display in the town. The town was occupied by the French army in 1675 and 1794, and was the scene of fierce fighting in 1914 as the German army swept through Belgium on its way to France.