A stave church is a medieval wooden church constructed with posts and lintels (as opposed to, for instance, a loghouse construction). In Old Norse the vertical posts were called stafr (the modern Norwegian word is stav), which is where the stave churches get their name. Probably around 2000 stave churches have been built in Norway, but today only 28 are left.
Urnes stave church, in Ornes at the south of Lustrafjorden, is the oldest stave church still standing: the timber used for the church was cut down around 1129-1130. The church we see today is the fourth stave church on this location.
The cylindrical columns with cubic capitals that we can see inside the Urnes church — and outside — probably look the way they do in an attempt to imitate contemporary Romanesque stone architecture further south in Europe.
The famous portal on the north wall, with the animal-ornamentation carvings is originally from one of the earlier churches, and is in a style which is now often referred to as Urnes style.