Fredrikstad Cathedral stands in the New Town (Nybyen), the 19th-century part of the city that grew up on the east bank of the Glomma once the military restrictions on development were relaxed. The building is a solid example of Norwegian neo-Gothic church architecture, with a prominent tower that serves as a useful landmark when orienting yourself in the town.
The interior rewards a visit mainly for the Emanuel Vigeland stained-glass windows, which date from the early 20th century and display a richness of colour and technique that distinguishes them from the average Norwegian church interior. Vigeland worked extensively with glass-painting using Roman and medieval techniques that he studied in Italy, and the results here are among his best. The cathedral is usually open during daylight hours.