Nidaros Cathedral (Norwegian: Nidarosdomen / Nidaros Domkirke) is a cathedral of the Church of Norway located in the city of Trondheim in Trøndelag county. It is built over the burial site of King Olav II (c. 995–1030, reigned 1015–1028), who became the patron saint of the nation, and is the traditional location for the consecration of new kings of Norway. It was built over a 230 year period, from 1070 to 1300 when it was substantially completed. However additional work, additions and renovations have continued intermittently since then; the most recent changes were completed in 2001. Nidaros was designated as the cathedral for the Diocese of Nidaros in 1152. After experiencing the turmoil and controversies of the Protestant Reformation of the 16th century, it was taken from the Catholic Church by the newly established state Church of Norway in 1537, which adopted the teachings and reforms of Martin Luther, Phillip Melancthon and others, becoming an Evangelical Lutheran church. Nidaros is the northernmost medieval cathedral in the world.
The cathedral is the main church for the Nidaros og Vår Frue parish, the seat of the Nidaros domprosti (arch-deanery), and the seat of the Bishop of the Diocese of Nidaros. The Preses of the Church of Norway is also based at this cathedral. The large, stone church seats about 1,850 people and it was historically used as the site of coronation of the kings of Norway.