St. Petri, Mühlhausen/Thüringen, Gothic church in Mühlhausen, Germany.

St. Petri is a stone church with a three-nave interior under vaults: the central nave has a barrel vault with painted ribs, the north aisle cross-ribbed vaults and the south aisle segmental transverse vaults. A half-timbered tower section with a tall, needle-like spire rises above the sacristy, and the steep roof is covered in glazed coloured tiles. Inside, pale stone columns line the nave, and the dark wooden baroque altar stands before three tall stained-glass windows.

The church's origin goes back to 1250, when it was built as a chapel of thanks for Mühlhausen's victory over the counts of Regenstein and Hohenstein. The Teutonic Order enlarged it from 1352 to 1356, and Archbishop Gerlach of Mainz re-dedicated it on 8 October 1356. After the 1422 city fire, the vault collapsed and was replaced by flat ceilings; the neo-Gothic renovation by Gottfried Koethe followed in 1893–1895.

The baroque altar and pulpit were made by the local Ackermann joinery in 1746–1748, and descendants of that workshop still work in the parish. The altar is flanked by Peter and Paul, with a Last Supper scene at its centre and the risen Christ at the top; its side wings were removed in a 1980 restoration. The north chapel holds a World War I memorial by the Mühlhausen sculptor Walter Krause showing the "Angry Christ" before a plaque of fallen soldiers' names, praised by Käthe Kollwitz.

The church is open to visitors who can explore the medieval architecture, attend religious services, or join guided tours. It is best to check opening times beforehand to ensure unobstructed access to the building and its spaces.

The baroque altar was carved by the Ackermann joinery in 1746–1748, and descendants of that workshop still work in the parish today. Christ appears three times on it: crucified at the altar table, instituting the Last Supper in the centre, and risen in the crowning section. The side wings were removed in a 1980 restoration.