Hallgrímskirkja church is Reykjavík's main landmark and its tower can be seen from almost everywhere in the city.
It was designed by the late Guðjón Samúelsson in 1937, who was often inspired in his endeavours by the fascinating shapes and forms created when lava cools into basalt rock.
Construction of the church began in 1945 and ended in 1986, with the tower completed long before the rest of the building. The crypt beneath the choir was consecrated in 1948, the steeple and wings completed in 1974 and the nave consecrated in 1986.
https://visitreykjavik.is/hallgrimskirkja-church