Catholic town church and Sebastian's chapel with church treasure, Catholic church ensemble in Baden, Switzerland

The town church Maria Himmelfahrt is a three-aisled Gothic building erected in 1457–1460 by the master builders Hans Murer and Cunrat Zobrist, with a 52-metre tower completed in 1489–1493 by Martin Grülich and a spire of coloured tiles. The central nave, carried on octagonal pillars, keeps the width of the earlier church; the choir and the tower's lower three storeys date from the 14th century. The church treasure museum of the Baden parish, one of the most important in the canton of Aargau, is not in the Sebastian chapel on the southern slope, which served as an ossuary.

A parish in Baden is documented from 1241, over 50 years before the town's formal founding; a Carolingian predecessor church of the late 9th century was excavated in 1967/68. The present three-aisled Gothic church was built in 1457–1460 under master builders Hans Murer and Cunrat Zobrist, and the tower followed in 1489–1493 by Martin Grülich. In 1526 the Badener Disputation between Johannes Eck and Johannes Oekolampad took place here, and the town remained Catholic.

The church is dedicated to the Assumption of Mary, documented as patroness by the 14th century; since 1650 Damian, a catacomb saint whose bones Pope Innocent X gave to the church, has been second patron. From 19 May to 8 June 1526 the Badener Disputation between Johannes Eck and Johannes Oekolampad took place here, the first disputation of the Zwinglian Reformation outside Zurich.

The church and chapel are easily accessible on foot through the center of Baden. It is recommended to allow plenty of time to view the displayed artworks and architectural details at a comfortable pace.

The church treasure museum of the Baden parish holds one of the most important church treasures in the canton of Aargau. Since 1650 the church has also kept the bones of the catacomb saint Damian, a gift from Pope Innocent X, who became its second patron alongside Mary.