Grand Masters of the Teutonic Order was built below the church and decorated with stucco by Roth, but it was desecrated and the graves were destroyed around 1809. Outer ring One of the last buildings constructed on the palace grounds before its secularization was the chapter house, erected in 1780. It was commissioned by Grand Master Charles Alexander of Lorraine in 1776 and was designed by Franz Anton Bagnato, master builder of the Teutonic . The decoration of the hall's interior is military in character, with stucco reliefs of timpani, trumpets, trophies of arms, and representative symbols for the continents of Europe, Asia, Africa, and the Americas. The illustrations in the chapter house generally glorify the history of the Teutonic Order. Gardens Mergentheim Palace has had a garden since at least 1600, when a court garden was laid out on the southern and eastern edge of the palatial grounds. From 1739 to 1745, Grandmaster Bayern had that garden replaced with a French-style garden that included an orangery and a pavilion designed by architect François de Cuvilliés. This pavilion was demolished in 1823. In 1791, Grandmaster Maximilian Francis of Austria decided replace the existing gardens with an English landscape garden. The path the garden would be laid out around was completed in 1800, while work on the garden itself was completed by 1804–05. This garden also included two new pavilions completed in 1802. A portion of the palace gardens lies on the right bank of the Tauber, away from the palace. Museums In 1864, Carl Joseph von Adelsheim's collection of antiquities was donated to the city of Mergentheim per his will. According to Adelsheim's wishes, the collection was displayed in a room in Bad Mergentheim's town hall, and it was expanded in subsequent years by donations. The collection was moved into Mergentheim Palace in 1927 and three years later gained the sponsorship of local history association and was rebranded into a local history museum. The focus of the museum shifted to the history of the Teutonic Knights after World War II. After a four-year renovation between 1969 and 1973, the palace museum reopened as the . The museum was further enlarged from 1990 to 1996 to fill the entire residential building, bringing it to a size of . The second floor of the residential building is filled by the exhibit dedicated to the history of the Teutonic Knights, and their legacy