Zelená Hora, Baroque château in Klášter, Czech Republic

Zelená Hora is a château in Klášter, north of Nepomuk, built on the site of a medieval castle. The three-storey building forms a horseshoe plan with a tower in the east wing, and its pale walls are pierced by rows of small rectangular windows. A tall clock tower with a steep, dark spire rises from the long, low-pitched reddish roof.

A castle was first documented on the hill in 1221, when Ottokar I Přemysl exempted the Nepomuk monastery's estates from labour to build castles including Zelená Hora. After the Hussite wars, Hynek Krušina of Švamberk began a new castle, finished in 1454. On 28 November 1465 the Black Hall hosted the founding of the Zelenohorská jednota, an alliance of 16 noble families against King George of Poděbrady.

The castle is known for the Zelenohorský Manuscript, allegedly found here in 1817 and later exposed as a forgery by Václav Hanka. The 1992 film Černí baroni was shot at the castle, and the building remains a setting for its story.

The château stands on Zelená hora (536 m) one kilometre north of Nepomuk, in the cadastre of Klášter, above the confluence of the Mihovka and the Úslava. The municipality of Klášter took over the site in 1992 and has been reconstructing it gradually; in 2025 the mayor said the village could not afford its upkeep, and the property was sold that November to the timber firm KLAUS Timber. Check opening conditions before setting out.

The castle's well was fed by a waterworks drawing water from the former monastery mill through wooden pipes, considered probably the oldest in Bohemia. The 1992 film Černí baroni was shot here, based on Miloslav Švandrlík's novel set at the castle.