The origins of Celles date back to the 2nd century when the region worshiped the Roman god Neptune. In the 7th century, the region was evangelized by Saint-Hadelin who founded a monastery.
When he died in 690, his companions locked his body in a shrine which they walled up in the current western crypt of the church.
Several miracles being attributed to the Saint, the village became an important pilgrimage center.
Almost 1000 years ago, the monks decided to build the church as it can still be seen today. In 1337, undergoing the harassment of the Lords of Celles, the monks left the village to take refuge in Visé near Liège, taking with them the relics of the Saint.
Today, locals are still very attached to their patron Saint, whose feast is celebrated on February 3.
Rue Saint-Hadelin, 12