Königstein is the ruin of a hilltop castle above Küttigen in the Swiss canton of Aargau. It is located at 610 meters on the Brunneberg in the Folded Jura, around 150 meters above the bankers' hill through which the road leads to the Benken.
The castle was built in 1277 by the lords of Kienberg-Küngstein, a small bailiwick that included Küttigen and Erlinsbach. The lords of Kienberg-Küngstein sold it to the city of Aarau in 1417. Since in 1535 the rule of Königstein, which had belonged to the Bernese state association since 1415, fell directly to Bern, it became part of the Biberstein bailiff. In 1798, Küttigen, and thus also the castle, was added to the Helvetian canton of Aargau, to which it belonged from 1803. Today the ruin is owned by the local community of Küttigen.
According to a legend, the lord of the castle is said to have forced the Küttig farmers to deliver him a large amount of leather in order to build a suspension bridge to the Achenberg. He wanted to visit his lover on horseback, who lived there in the (historically not documented) Urgiz Castle. After he had the bridge built, a courageous farmer is said to have slightly cut the ropes of the bridge in a night-and-fog operation, so that the lord of the castle fell with his horse in the middle over the gorge.
As old farmers still tell each other, deep under the ruins, hidden in the well, the cruel people-flayer's treasure is buried. Some are said to have found old gold coins there that turned into snail shells on the way home. Even more, however, is said to have met nothing but a copper snake whose bite causes the limbs to wither. Legend has it that the walls are so shaky that you can rock them with your bare hands. However, no one could overturn it, not even with the heaviest of equipment, since the best milk was used to mix the mortar, which the lord of the castle had forced from the farmers.