The Abbatiale Saint-Silvin and Saint-Georges testifies to the long monastic past (Benedictines circa. 670-881, then Benedictines 1072-1791) of the village long named Auchy-les-Moines. Most of the interior elements of the abbey are classified as Historical Monuments and the building is inscribed there. The pillars of the nave date from its foundation in the 12th century. Very vast at its peak, in the 13th and 14th centuries, then victim of the conflicts of the 15th and 16th centuries, the abbey was almost in ruin around 1600. In the second half of the 17th century it was rebuilt in its present dimensions. Most of the furniture that can be seen today (stalls of monks, woodwork and altarpiece of the choir, high altar, organ) was installed there around 1680-1720. Above the altar a "Descent of the Cross" is attributed to Van Dyck (1599-1641) or to his workshop. The side altars, the stained glass windows, the Way of the Cross, the baptismal font, date from the second half of the 19th century. There are also: - the tombstone of Count Enguerrand of Hesdin, founder of the abbey in 1072 - a commemorative plaque of French lords and knights killed at the battle of Azincourt (1415) and buried in the abbey.