The original Wiltz castle was situated in the lower town where the parish church is located nowadays. Though it was supposed to protect the town from its enemies, its location was so badly chosen that it kept being overrun. Therefore -in the late 12th Century- the lords of Wiltz built another larger castle on a rocky promontory above the banks of the river Wiltz. This part of town is now Oberwiltz.
In 1388 the castle and town were set on fire by the French besiegers and a new larger rampart was soon rebuilt. By the middle of the 15th Century when the Oesling nobility fought against Philip of Burgundy's invasion, the castle was destroyed a second time.
The oldest part of today's castle is the round “Witches Tower” on the northwest side. It was built in 1573 and subsequently restored twice. Since the 19th Century, Count Jan -the legendary armoured knight whom the good people of Wiltz have chosen as their eternal guardian- graces the roof of the multistory tower. The square tower dates from 1626, though it's built on older foundations. This tower used to be the main entrance, reached over a drawbridge. To the right of this bridge stood the “justice lime” hence the square outside the castle is still called “Lannepesch”.
On May 23, 1631, John VI of Wiltz (aka Count Jan) began building a new castle in the Renaissance style at the same location. The Thirty Year War, various sieges, famine and epidemics, however, were delaying the works by nearly a century. And so it was that Count Charles-Eugene de Custine, husband of Marie Françoise Xavière d'Arnoult, completed the castle only in 1720.
In 1722, the new chapel was built. Five years later, the magnificent staircase leading up to the castle gardens was completed. Since the 1950s it has served as the backdrop for the world famous Wiltz Festival featuring open air music and theatre.