The interior of the St. Gerlach Church (Sint-Gerlachuskerk) in Houthem, near Valkenburg aan de Geul, stands as a premier masterpiece of late Baroque architecture and South German Rococo artistic style within the Netherlands. Originally built as part of a Norbertine nunnery, the church is uniquely renowned for its expansive, immersive frescoes that cover virtually every vertical and vaulted surface.