Tournai is one of the oldest cities in Belgium, sitting on the Scheldt River just 10 km from the French border. The Romans established it on the road from Cologne to Gaul, and the Merovingian Franks later chose it as the seat of their kingdom — Clovis, founder of the Frankish state, was born here in the fifth century.
The star attraction is the Cathedral of Our Lady, a UNESCO World Heritage Site and one of the most spectacular churches in Belgium, with five towers and a blend of Romanesque and Gothic architecture. The city centre is compact and walkable, with a fine Grand Place and several good museums, including one dedicated to tapestry — a local speciality for centuries. Another famous native is the Flemish master painter Rogier van der Weyden.
Tournai is easy to reach from Lille, Brussels, or Ghent, making it a good day trip — though it deserves more than a few hours.