The church of St. Johann whose construction began around 1000. At the end of the 14th century, a new Gothic church with three naves was built. The basement of the church contains the well-preserved remains of the previous Romanesque churches. One day after the introduction of the Reformation in 1529, the paintings and altars were destroyed. The baroque stucco ceilings of the central nave and the interior side aisles were made by Johann Jakob Schärer (1667-1746). The church was last renovated in 1990.
The Münster was first built in 1064 as the Romanesque basilica of the Kloster Allerheiligen, then owned by the Benedictines. After centuries of economic and political decline, Michael Eggendorfer, the last abbot of the monastery, initiated the last renovations in 1521-22. During the Swiss Reformation, the abbey was abolished and the Münster became the second main church in the town in 1524.
The parish of St. Konrad was first mentioned in a document in 1487. After the Thirty Years' War, the clergy of Villingen helped to restore pastoral care in Rietheim and donated liturgical material from the small church, which had been burnt down by Württemberg soldiers on 6th July 1633. In 1671 the church was renovated. In 1719, the Kirchdorf priest Jakob Diem had the present baroque choir built. In 1809-10 the sacristy was added. The church was extensively renovated in 1830-1833 and again in 1861-62. In 1873-74, the interior was renovated and the church received a high altar and pulpit in neo-Gothic style, as well as new pews.