The castle hill was already inhabited in the Bronze Age.
Gräpplang Castle was built in 1220 by the Knights of Flums.
In 1440, during the Old Zurich War, the castle was blackmailed by the Glarus and the Schwyz for protection money, but was never attacked militarily.
In the 17th century, the complex was structurally altered under Josef Anton Tschudi.
In 1767, the Tschudi family sold Gräpplang to the Good family, but it seems that they hardly ever lived in the dilapidated castle.
In 1804, the castle was sold to Josef Eberli in Flums for demolition. In the following decades, the stones from Gräpplang were used to repair buildings in the vicinity of the castle and the roof tiles were used to repair the church in Vilters.
From 1914, the local tourist office carried out the first repairs.
Between 1990 and 1991, extensive conservation work was carried out on the castle for the last time.
In 1998, the interior of the palace was completed with a narrow staircases to make it more accesible for visitors.
The Castle Gräpplang is located 450 meters above sea level in Flums, Switzerland.