Släbro is without question one of Sweden’s greatest and most remarkable rock carvings site. Situated near the River of Nyköping the carvings were discovered 1984 and can be dated back to the Bronze Age. They are unique because they are carved in a most unusual way. There are etchings on some ten different surfaces with a total of some 700 figures, mainly frame and circle figures. Many are unique in design, in particular the large stylised human figures in a position of adoration. The characteristics commonly found throughout carvings in the South of Sweden are missing. What is more, the Släbro carvings seem to bear no similarity to any other ancient carvings that have been discovered throughout Europe. The carvings date from 1800 – 400 BC and thus far the meaning behind them remains something of a mystery as it has proven to be extremely difficult to interpret the motif as it appears in literally hundreds of different ways.References:
Ängsö Castle was first named as "Engsev" in a royal charter by king Canute I of Sweden (r. 1167-1196), in which he stated that he had inherited the property after his father Eric IX of Sweden. Until 1272, it was owned by the Riseberga Abbey, and then taken over by Gregers Birgersson.
From 1475 until 1710, it was owned by the Sparre family. The current castle was built as a fortress by riksråd Bengt Fadersson Sparre in the 1480s. In 1522, Ängsö Castle was taken after a siege by king Gustav Vasa, since its owner, Fadersson's son Knut Bengtsson, sided with Christian II of Denmark. However, in 1538 it was given by the king to Bengtsson's daughter Hillevi Knutsdotter, who was married to Arvid Trolle.
In 1710, the castle was taken over by Carl Piper and Christina Piper. Ängsö Castle was owned by the Piper family from 1710 until 1971, and is now owned by the Westmanna foundation. The castle building itself was made into a museum in 1959 and was made a listed building in 1965. It is currently opened to visitors during the summers.
The castle is a cubical building in four stores made by stone and bricks. The lower parts is preserved from the middle ages. It was redecorated and expanded in the 1630s. The 4th storey as well as the roof is from the expansion of Carl Hårleman from 1740-41. It gained its current appearance in the 1740s.