Although the buildings in Helsinki are not a thousand years old, its religious buildings display the diversity of modern architecture, of which Helsinki is one of the world's capitals.
Temppeliaukio Church is a modernist monolithic stone church, completed in 1969. The church, carved into the rock, was designed by the brothers Timo and Tuomo Suomalainen and is an outstanding example of architectural expressionism of the 1960s. It is made of granite stone which allows daylight to filter through the roof. Thanks to its acoustic properties, the church is a popular concert venue.
The Helsinki Synagogue is an Ashkenazi synagogue built in 1906 by the architect Jac Ahrenberg (1847-1914). The exterior architecture of the three-storey building follows Art Nouveau, as well as the eclectic style common in Central Europe and England at the end of the 19th century. The interior has been exceptionally well preserved in its original appearance. There are rectangular concrete pillars with gilded Art Nouveau details in the capitals. The vertical supports of the gallery balustrades are also decorated with Art Nouveau style metal ornaments.
The Kamppi Chapel, or the Chapel of Silence, was built in 2012. The chapel is part of the Helsinki Design Capital Year projects and was designed by architect Mikko Summanen. The chapel won The Chicago Athenaeum: International Architecture Awards for The Best New Global Design Award 2010. The chapel does not actually hold religious services but is a place where silence can be found.
The Old Church of Helsinki is the oldest church in Helsinki city centre, completed in 1826 by the architect Carl Ludvig Engel. The Old Church was originally intended only as a temporary solution when the 18th century Ulrika Eleonora Church, which was replaced by Helsinki Cathedral, was demolished to make way for the Senate square. Due to the temporary character, the old church was built of wood and without bells. The Old Church is surrounded by the Old Church Park, which was a former cemetery.
The church of Mikael Agricola is a brick church built between 1933 and 1935 in the functionalist style. A design competition was held for the construction of the church in 1930. Out of 56 proposals, the award committee chose the design by the architect Lars Sonck (1870-1956). Since the Lutheran church was built, as its name suggests, the Anglican Church of Finland has also held services on the premises of the Mikael Agricola Church.
St. John's Church is a church built between 1888 and 1891 by Stockholm architect Adolf Emil Melander. The church is one of the most outstanding examples of neo-Gothic churches in Finland. The church was damaged during the great bombing of Helsinki in February 1944; among other things, several windows were broken. The church was restored for its centenary, and then part of the old decorative paint layer was exposed on the gallery wall.
The German church was built in 1864 and designed by Harald von Bosse and C. J. von Heideken in the neo-gothic style. The church burnt down in 1958 and was then repaired according to the plans of architect O. Hansson. Between 1997 and 2001 the church underwent a major renovation, modification and extension of the buildings, designed by architects Juha Leiviskä and Rosemarie Schnitzler.
Helsinki Cathedral is a cathedral of the Evangelical Lutheran Church of Finland located in the centre of Helsinki. It was built between 1830 and 1852 when Finland was part of the Russian Empire (1809-1917) and was called St. Nicholas' Church. As early as 1818, Carl Ludwig Engel, who worked on the design of the whole square, drew the first plans of the church and refined them over a decade. The cathedral replaces the former Ulrika Eleonora church. The church did not officially become a cathedral until 1959 when the Helsinki Diocese was established.
The Church of the Holy Trinity is an Orthodox church designed by Carl Ludvig Engel, consecrated in 1827. The church is an example of the Imperial style and serves the large Russian-speaking Orthodox minority in Helsinki, partly because the other Orthodox churches in the city have held their services in Finnish. The top of the church's bell tower was originally made of wood, but twenty years after its construction it was rebuilt in the present stone, when new heavy bells were added to the church.
The Cathedral of the Assumption, or Uspenski Cathedral, is the cathedral of the Orthodox Diocese of Helsinki. It was built by order of Emperor Alexander II of Russia between 1862 and 1868. It was designed by the architect Alexis Gornostaiev (1808-1862), one of the founders of the Russian Revival architecture. The crypt hosts a variety of events, including exhibitions and lectures on ecclesiastical art and ecclesiastical artefacts.