Vítkův hrádek, Castle ruin in Dvoreček, Czech Republic

Vítkův hrádek is a ruined medieval castle on a promontory above the Hamerský potok stream near Blažejov. Its triangular core was protected by a double ditch and rampart, and remains include a round bergfried and wall sections 1.15–1.35 m thick built in opus spicatum.

Founded in the first half of the 13th century by the lords of Hradec, likely under Vítek z Hradce, the castle was first documented in 1267 when Vítek II of Hradec transferred it to the German Order. By 1416 it was held as a pledge by Sezema of Chotěnice, and in 1458 it was listed as deserted.

The castle's German names Veitschlössel and Pittenhäusel survive in local usage. From the early 15th century the estate was attached to the church of St. Elizabeth in Blažejov, and the castle itself was probably no longer inhabited.

The ruins lie on a spur above the Hamerský potok valley north of Blažejov, reached by a short side path off the red-marked hiking trail running through the valley from Malý Ratmírov to Jindřichův Hradec. The site is freely accessible; the terrain is uneven and overgrown, so sturdy footwear helps.

The castle core was protected by a double moat and rampart, and part of the residential palace wall was built in opus spicatum, a herringbone masonry technique visitors can still trace in the surviving stonework.