Janštejn Castle, Castle ruin in Nová Ves, Czech Republic

Janštejn Castle is a ruin set on elevated terrain near Nová Ves with stone walls and foundations still visible. The remains clearly outline the original layout of the medieval fortification.

The castle was founded around 1315 by the lords of Březnice as a bergfrit-type castle. In 1358 Štěpán of Březnice sold it to the Moravian margrave Jan Jindřich, and Margrave Jošt granted it as a fief to Ondřej of Meziříčí. In 1383 the brothers Jan and Jaroslav of Meziříčí sold Janštejn to Jindřich of Hradec; it probably disappeared around the turn of the 15th century.

Local legend holds that Nová Ves was founded after Jan Žižka destroyed the castle, though the sources record the castle's decline around 1400. The site is protected as a cultural monument of the Czech Republic.

The ruin lies in woodland on the slope between Horní Dubenky and Nová Ves, in the cadastral area of Nová Ves; the surviving masonry stands on raised ground above the forested remains of the farmyard at its foot. The slender tower had a diameter of 4.7 m and walls 2 m thick, so the core of the site is compact and quickly walked. The first proper archaeological excavation began only in 2025, so expect unkempt ground rather than furnished paths.

The remaining walls show a transition between early Gothic and late medieval building styles. This blend of architectural periods is rarely this visible in the region.