The tour includes explanations of the altar of the organ, as well as the princely tomb under the church.

The castle church of St. Trinitatis still bears witness to its former splendour. Its history is closely connected with musical personalities such as Georg Friedrich Händel and Johann Sebastian Bach. This is how Handel's talent for the organ was discovered. Johann Sebastian Bach bore the title of "Weißenfels Court Kapellmeister by birth" and composed the hunting and shepherd cantata for Duke Christian of Sachsen-Weißenfels. He composed his Toccata in F major for the organ of the castle church of Weißenfels. The organ work of the former Förner organ from 1673 was renewed by the Voigt company in 1985. The foundation stone of the castle church was laid in 1663. The stucco work was done by Giovanni Caroveri and Batholomeo Quadri. The pulpit altar was designed by the Schneeberg artist Johann Heinrich Böhme the Elder In 1682 the church was consecrated. Below the chancel is the princely crypt of the Dukes of Saxony-Weissenfels and their families. 38 state coffins, 28 of them made of tin and ten wooden coffins were placed in the crypt between 1669 and 1775. From 1991 to 1995, extensive restoration and restoration measures took place.