Senate Square (Senaatintori) presents Carl Ludvig Engel's architecture as a unique allegory of political, religious, scientific and commercial powers in the centre of Helsinki. It has been the centrum of Helsinki since the city was established in 1640. Russians destroyed Helsinki entirely during the Great Northern War (1713-1721).
When the Finland became an autonomous part of Russia in 1812, the capital was moved from Turku to Helsinki. This started a massive construction programme to enhance the cityscape of Helsinki. The responsibility of the new design was given to German architect Carl Ludvig Engel. He decided that all buildings surrounding the old main square should be reconstructed to solid neoclassical ensemble. Many old buildings were demolished including the church of Ulrika Eleonora.
The Palace of the Council of State was completed on the eastern side of the Senate Square in 1822. The main University building, on the opposite side of the Senate Square, was constructed in 1832. The Helsinki Cathedral on the northern edge of the Senate Square was Engel's lengthiest architectural project. He was working on it from 1818 until his death in 1840. The Helsinki Cathedral — then called the Church of St. Nicholas — dominates the Senate Square, and was finalized twelve years afters Engel's death, in 1852.
A statue of Emperor Alexander II is located in the center of the square. The statue, erected in 1894, was built to commemorate his re-establishment the Diet of Finland in 1863, as well as his initiation of several reforms that increased Finland's autonomy from Russia. The statue comprises Alexander on a pedestal surrounded by figures representing the law, culture and the peasants.
Today, the Senate Square is one of the main tourist attractions of Helsinki. Various art happenings, ranging from concerts to snow buildings to controversial snow board happenings, have been set up on the Senate Square. Several buildings near the Senate Square are managed by the government real estate provider, Senate Properties.
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.