The St. Agatha and St. Gertrudis Chapel in Fleckenberg is the oldest building in the village, still largely preserved in its original state. Not least because of its painting and the preserved furnishings, it was entered in the list of monuments of the town of Schmallenberg on December 10, 1992. Probably already in the year 1665 some farmers of Oberfleckenberg began with the construction of this church, which was solemnly consecrated on October 10, 1666.