Arna is a borough in the city of Bergen in Hordaland county, Norway. Arna is one of 8 boroughs in Bergen. It encompasses the northeastern part of the municipality of Bergen. Arna was merged into the city of Bergen in 1972. Prior to that time, it was the separate municipality of Arna. The main population centres in the borough are the villages of Indre Arna, Ytre Arna, and Espeland.