The royal castle on the southern tip of Visingsö in Lake Vättern, called Sweden’s first castle of the realm, where four kings died between 1167 and 1290.
Näs Castle was a Swedish royal fortress on the island of Visingsö in Lake Vättern, serving as an important administrative residence for medieval Swedish kings. Erik Knutsson died there in 1216, leaving a young heir and prolonging Swedish dynastic instability.
It stood at the southern tip of the island, where the water is widest and a garrison could see anyone coming for half a day. Swedish historians have called it the first riksborg, the first castle built for the kingdom rather than for a district, and the kings kept the realm’s valuables there.
Visingsö lies in the middle of Lake Vättern, between Götaland and Småland, and a lake in the twelfth century was a road rather than a barrier. A castle on the island sat in the middle of the traffic and out of reach of any force without boats, which is exactly what a king with domestic enemies wanted.
The building is dated to the twelfth century and attributed either to Sverker the Elder or to his son Charles VII Sverkersson. It was a royal seat, a treasury and a refuge, and both of the families contesting the Swedish crown used it in turn.
Four kings died on the island, which is a remarkable concentration for a kingdom whose rulers usually died on campaign or in bed at a dozen scattered estates. Charles VII Sverkersson, who had made the castle his residence, was killed on Visingsö on 12 April 1167 by men supporting Knut Eriksson, who took the crown from him.
Erik Knutsson died at Näs on 10 April 1216, of illness, at the height of his success and a few years after winning the crown in the field at Gestilren. His son was born after his death, so the throne passed to his rival’s son John I Sverkersson — who died at Näs in turn on 10 March 1222, aged about twenty and the last of his house. Magnus III of Sweden, known as Magnus Ladulås, died there on 18 December 1290.
The castle’s working life ended in the wreck of Birger Magnusson’s reign. In 1318, with the kingdom in revolt against him after the killing of his brothers at Nyköping, Birger pledged Näs to the Danish king, and the castle was burned after fighting on the island that same year while Birger was in exile.
Nothing was rebuilt. Swedish royal power had by then moved to Stockholm and the castles of the Mälaren, and an island fortress in Vättern had no further use.
The remains measure roughly 32 by 12 metres: a round tower and a four-sided tower joined by a length of wall, built of slate and sandstone, standing three to four metres high and between one and one and a half metres thick.
The ruin has been consolidated and restored, and is a protected ancient monument. It is the oldest surviving royal castle ruin in Sweden, and the only medieval structure on an island otherwise known for its seventeenth-century oak plantations.