St. Nicholas Church with its Romanesque tower and Baroque helmet from 1700 is a typical Westphalian hall church from the transitional period from Romanesque to Gothic style. It was built around 1300 and is dedicated to St. Nicholas, which indicates a surrounding medieval merchant settlement. Its impressive baroque furnishings are mainly the result of contemporary donations. Donations from the citizens of Rüthen.
The building is a short, two-bay hall church with a short connecting bay to the square west tower. It was built in the third quarter of the 13th century with dressed rubble stone. The one-bay choir with 3/8 closure dates back to around 1300. The east sacristy is marked 1700 and was later raised. The upper storey of the tower, crowned with a baroque helmet, was added in 1712. The church has an oblique ground plan. The central nave bays are almost square in shape. The eastern bay has cruciform piers with semi-columned mouldings and stylized foliate capitals. In the west there are strong round piers and towards the tower hall there are bundle piers. Walled wall apses can be seen in the side aisles. The original vaults of the central nave were removed in 1833 and later replaced by ridge vaults. In the side aisles, intercepted services support single-hip stab cap vaults. The walls in the nave are divided by round-arched windows, those in the tower with pointed-arched ones. The choir was equipped with one- and two-piece tracery windows. On the early Gothic tower portal the pillars were renewed. The southern portal with a sprung gable and figure niche is marked 1712. On the north side of the tower, a spiral staircase emerges to the outside. The partially unused bundle piers between the hall and the tower indicate a High Gothic remodeling project that was started and not continued.
The organ was probably installed in 1756 by Adolph Cappelmann from Geseke. It was rebuilt in 1875 by August Randebrock. A new organ was built in 1936 by Anton Veith using the old pipe stock. Siegfried Bauer renovated extensively in 1999. The old bellows were reactivated, new slider chests were installed. Nine stops by Randebrock and Veith were preserved. The lateral console was renewed and the gallery was lowered to achieve a better sound radiation. The organ was damaged by smoke in 2002 and then repaired.