Freudenstein Castle lies outside the borders of the protected heritage area of the town on a hill above the north-western edge of the settlement. The castle was built by Stephan Schlick in 1516–17 to protect the town. Records indicate that the first Joachimstalers, unauthorised local coins, were minted illegally in the cellars of the castle in 1519. In 1548, the castle came into royal possession and was used as the seat of the royal mining overseers. During a siege by the Swedish army in 1636, the castle was seriously damaged by the artillery and destroyed by fire. The castle was abandoned and slowly decayed. Only the two towers remained standing. The large tower in the north-west corner, known as the Schlick Tower, still stands at its full height of 19 metres. There is a 12-metre round tower in the south-west corner, which previously served as the powder house where gunpowder was stored for use in mining.