Schloss Marienthal, Cultural heritage monument in Eckartsberga, Germany.

Schloss Marienthal is a castle with baroque three-wing layout located near Eckartsberga. The south-facing section displays neo-baroque and early classicist architectural features across two stories.

The castle was built in 1730 on the grounds of a former monastery as a residence for the Münchhausen family. Ownership later passed to the von Seebach family and eventually to the von Wilmowsky line.

The south wing retains decorated interiors from the early 20th-century rebuild, including a library and a staircase. The architect Paul Schulze-Naumburg designed this wing in 1913/14 for Tilo Freiherr von Wilmowsky and his wife Barbara Krupp, née Krupp. The Marienthal park, also under heritage protection, belongs to the estate.

The castle is privately owned and protected as a cultural heritage site, so it is worth checking in advance whether visits are possible. The best time to see it is during dry weather when the facade and grounds are fully visible.

The last remains of the so-called Old Castle were demolished in 1950, after part of it had already been torn down in 1910. The present south wing was rebuilt in 1913/14 by architect Paul Schulze-Naumburg for Tilo Freiherr von Wilmowsky and his wife Barbara Krupp. Since 1996, much of the complex has belonged to the Schreiber family.