Søborg Castle

Søborg Castle (Danish: Søborg Slot), in its heyday, was the strongest castle in Denmark, and was also used as a prison (Jens Grand was imprisoned here in the 13th century). It was inhabited until the Count's Feud in 1535, when it is speculated that it was destroyed. In 1577, the feudal tenant was granted permission to use the ruins as a quarry.
History
Søborg Castle is first known from the 12th century, when ownership of the castle passed from the king to the bishop of Roskilde.
Traditionally archbishop Eskil of Lund is said to have expanded the previous buildings to a real castle with defensive walls and a moat. As Eskil was in close contact with Esrum Abbey, it is considered likely that he lived nearby at Søborgby. Saxo Grammaticus wrote that Eskil had built a castle in the den lethriske mose, but it is unknown whether that is a reference to Søborg. No-one has so far been able to make a clear connection between Eskil and Søborg...