Ehemaliger Schloss- bzw. Kavaliersbau der Reichsgräfin von Tilly-Montfort, Heritage castle in Breitenbrunn, Germany.

The Tilly-Schloss is a two-storey building with a symmetrical facade and mansard roof in late Baroque style, located above Von-Tilly-Straße 7. It has a decorative portal and an eastern wing added for the Pflegamt, which distinguishes it from the neighbouring Gumppenberg-Schloss built in 1746.

Maria Anna Katharina, Countess of Montfort, born T'Serclaes von Tilly, had the palace built around 1733 (or 1740) after withdrawing from nearby Breitenegg Castle, which had been enfeoffed to her great-grandfather Johann T'Serclaes von Tilly. From 1806 it housed the Pflegamt Breitenbrunn, previously seated at Breitenegg, and later the state forestry office, a school and the town hall. In 2010 local historian Kurt Martens showed that the two neighbouring palaces had long been confused: only this eastern one has the east wing the countess added for the Pflegamt.

The Tilly Festival has been held annually since 1988, first organised by the Breitenbrunn trade association and taken over by the municipality in 1991. It takes place on the "Zigeunerlager" area in front of the neighbouring Gumppenberg Castle, long mistaken for the Tilly Castle, and at the "Kasten" on the market square. Costumed performers stage the storming of the town, followed by a fireworks display, a parade, archery and a children's tournament; in 2019 it received the Heimatpreis Bayern.

The building stands at Von-Tilly-Straße 7, directly beside the Gumppenberg-Schloss at number 5, which was added in 1746. It is listed as a protected monument under file number D-3-73-115-77. The interior is not open to visitors; the two neighbouring buildings are best viewed from the street.

In 2010 local historian Kurt Martens established that the Tilly and Gumppenberg castles had long been confused. Only the eastern of the two buildings has an east wing, which Countess Montfort had added for the Pflegamt, so the wing identifies this house. Signs and online data had swapped the two for decades.