The church of Saint-Martin d'Habarcq has the particularity of being a building whose qualification has evolved over time. Rebuilt in the 16th and 17th centuries, this building was first a seigneurial chapel before being given to the commune in 1806 to become its parish church. This church is thus a double case unique in the department because it is also the only church to be attached to the castle of the family of its builders who took care of it during the conflicts that crossed the Artois during the fifteenth, sixteenth, and seventeenth centuries. The current church thus forms an ensemble with the castle because their facades merge in a same alignment that surprises the visitor.