Verla is a well-preserved 19th century mill village and a UNESCO World Heritage Site since 1996. The first groundwood mill at Verla was founded in 1872 by Hugo Nauman but was destroyed by fire in 1876. A larger groundwood and board mill, founded in 1882 by Gottlieb Kreidl and Louis Haenel, continued to operate until 1964.
The Verla groundwood and board mill and its associated habitation are an outstanding and remarkably well-preserved example of the small-scale rural industrial settlement associated with pulp, paper and board production that flourished in northern Europe and North America in the 19th and early 20th centuries, of which only a handful survive.
Verla museum is open for visitors from May to September, but the larger World Heritage Site area can be explored around the year.
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.