Kunžvart, Castle ruin in the Bohemian Forest, Czech Republic

Kunžvart is a ruined castle on a granite outcrop at 1,037 m on the eastern ridge of Strážný Mountain, 1.5 km northwest of Strážný. Its only stone building was a square keep with 10.55 × 10.65 m sides, walls 240 cm thick and a rounded west corner; the perimeter defence was wooden.

Kunžvart was first documented in 1359, when Charles IV confirmed Pešek of Janovice and his nephews as holders of the Vimperk estate. Its importance grew under Wenceslas IV, who allowed a branch of the Golden Trail to be routed through Vimperk with toll rights. Uninhabited by 1547 and damaged by fire in 1578, it was quarried for stone from 1575.

The ruins attract hikers and history enthusiasts who come to see medieval building techniques typical of the region. It shows how fortifications fit into the landscape and what daily life might have been like for those who lived there.

Reaching the ruins requires sturdy hiking boots and careful footing on uneven stone surfaces. Visitors should stay on marked paths to avoid getting lost and to protect the ancient walls from damage.

The tower's masonry was quarried away from 1575 for building material, and part of its portal lining later served as the entrance to farmstead No. 5 in Kořenný. The ruin has been protected as a cultural monument since 3 May 1958.