The Open-Air Museum contains 158 buildings from rural and urban Norway - from the Middle Ages to the 20th Century. Among the main attractions are Oscar II's Collection (the first Open Air Museum in the world!) with Stave Church from Gol (dated 1200), the medieval Raulandstua (from the end of the 13th Century) and 19th Century Apartment Building frrom Wessels gate 15 in Oslo. The rest of the Open Air Museum contains post-medieval buildings from rural and urban Norway:

The Countryside
The Old Town
Oscar II's Collection
The Apartment Building

An Open Air Museum is a distinct type of museum exhibiting its collections out-of-doors. The first open air museums were established in Scandinavia towards the end of the nineteenth century, and the concept soon spread throughout Europe and North America.

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The Countyrside

contains buildings from many parts of rural Norway.

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The Old Town

contains mostly buildings from Christiania (Oslo).