The Arctic Cathedral, formally known as Tromsdalen Church or Tromsøysund Church (Norwegian: Tromsdalen kirke or Tromsøysund kirke), is a church in the city of Tromsø in Troms county, Norway. The church is commonly nicknamed the Ishavskatedralen, literally "The Cathedral of the Arctic Sea" or "Arctic Cathedral". The church was built in 1965 in the Tromsdalen valley and it is a parish church and not, in fact, a cathedral as it is commonly called. The church is part of the Tromsøysund parish in the Tromsø arch-deanery in the Diocese of Nord-Hålogaland.
The church was designed by the architect Jan Inge Hovig and is built mainly of concrete. The main contractor for the construction was Ing. F. Selmer A/S Tromsø. Because of the church's distinct look and situation, it has often been called "the opera house of Norway", likening it to the famous Sydney Opera House in Sydney, Australia. The church is probably the most famous landmark in Tromsø, although Tromsø does have another church of interest, Tromsø Cathedral, which is noted for being the only wooden cathedral in Norway.
The groundbreaking of the church was 1 April 1964 and it was completed in 1965. The new church was consecrated on 19 November 1965 by the Bishop Monrad Norderval. The church is built out of cast-in-place aluminium-coated concrete panels.
In 1972, a glass mosaic was added to the eastern side, made by Victor Sparre. The church acquired an organ built by Grönlunds Orgelbyggeri in 2005, with three manuals, pedal, 42 stops, and 2940 pipes. It replaced the old opus nr. 12 organ delivered by Vestlandske Orgelverksted, Hareid, which had 22 voices and 124 keys.