Gnandstein Castle is considered to be Saxony's best-preserved Romanesque fortification. The castle was built as a Romanesque complex at the beginning of the 13th century, probably first with a rectangular ground plan and a residential tower. A 25-metre-deep well in the castle also dates from this period. Later, a well house was built to protect the well, but this was built over when the south wing was extended in the Gothic period.