It was quite common in the 17th century for citizens in the Mälaren valley to invest in the iron industry. The first bar-iron forge at Trångfors was established in 1628 by Adolf Willemson, a merchant from Västerås. It started off small, with just three workers.
In the latter half of the 18th century, the Strömsholm canal cut straight across the Trångfors estate and the old manor house had to be pulled down. The existing forge was built in 1799. Good use was made of the water from the canal: an enclosed timber trough from the canal provided water power for the forge hammer. When the Lancashire method was introduced in 1875, production rose sharply and peaked in 1900 at an annual output of 3,100 tonnes. But by 1915, the forge had been closed down.
One of the four Lancashire furnaces has been restored, and work is under way on the water-wheel and trough. The mumbling hammer has been given a new base. In time, the intention is to be able to demonstrate the pig-iron refining process and mixing of the melt in the forge.
A congenial room with a cosy open fire is available for hire for private functions and meetings. It has been set up in the former spark-machining workshop next door to the forge.
A room above the forge, which used to be a rest room for the forge workers between shifts, has now been converted into a meeting room. The murals on the walls were painted by Gunnar Hall. Next door to that is the charcoal storehouse, which dates from 1800. The charcoal wagons ran straight in here and tipped their load from the ramps at the top of the furnace.
The Trångfors power station on the other side of the river was built in 1898–9 by a firm of consulting engineers, Qvist & Gjers, of Arboga. A water trough was built at the side of the waterfall and it carried the water over a distance of several hundred metres to the works. The power station operated until 1988 and is now a museum. The original equipment has been preserved. The station has six horizontal turbines each generating an output of 400 hp. The generators were manufactured by ASEA and were awarded the “Grand Prix” at an international industrial exhibition in Paris in 1900.
Every August, there is a Trångfors open day when the building is open to visitors, who can also watch barges being locked through on the canal.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.