Katarina kyrka (Church of Catherine) was originally constructed in 1656–1695. It has been rebuilt twice after being destroyed by fires, the second time during the 1990s. The Katarina-Sofia borough is named after theparish and the neighbouring parish of Sofia.
Construction of the church started during the reign of Charles X of Sweden, and the church is named after Princess Catherine, mother of the king, wife of John Casimir, Palsgrave of Pfalz-Zweibrücken and half-sister of Gustavus Adolphus. The original architect was Jean de la Vallée. The construction was severely delayed due to shortage of funds.
In 1723 the church, together with half of the buildings in the parish, was completely destroyed in a major fire. Rebuilding started almost immediately, under supervision of Göran Josua Adelcrantz, the city architect, who designed a larger, octagonal tower.
May 17, 1990, the church burned down again. Almost nothing but the external walls remained. Architect Ove Hidemark was responsible for rebuilding the church, which was reopened in 1995. The new organ was built by J. L. van den Heuvel Orgelbouw in the Netherlands.
Several famous Swedes are buried in the cemetery surrounding the church, most notable the assassinated Foreign Minister Anna Lindh, nationally popular Dutch-Swedish singer Cornelis Vreeswijk and Sten Sture the Elder.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.