The former farming village Reitnau is located on the edge of the Surenmooses. It consists of a lower village at the foot of the ridge and the upper village on the first level. There, the widely visible Reformed Church occupies a prominent place. The church is now centrally located in the settlement area Reitnau-Attelwil. Both villages together with Wiliberg form the parish of Attelwil-Wiliberg-Reitnau.
Reitnau was around the year 1000 property of the supraregional Count of Lenzburg. They donated the village and church before 1045 to the convent Schänis in Gasterland (between Lake Zurich and Lake Walen). A local Meier managed this monastery property. 1415-1798 the parish Reitnau belonged to the dominion of the city of Bern and was reformed in 1528 by order of the sovereign. The church set fell in 1807 to pastor Samuel Eggenstein (in Reitnau in office 1785 until his death in 1825) and went from his family in 1850 to the canton of Aargau.
The church construction of Reitnau goes back according to the archaeological findings of the excavation of 1993 probably to the late 7th century and received in 1522 after several conversions and extensions its present form. 1900 was added as the last element of the tower. This is not primarily an art historical, but historically significant building exists.