Árbær was an established farm well into the 20th century, and the museum opened there in 1957. Árbær is now an open air museum with more than 20 buildings which form a town square, a village and a farm. Most of the buildings have been relocated from central Reykjavik.

Árbær Open Air Museum tries to give a sense of the architecture and way of life and lifestyles of the past  in Reykjavík and during summer visitors can see domestic animals. There are many exhibitions and events held at the Museum which highlight specific periods in Reykjavik's history. These include craft days, vintage car displays, Christmas exhibitions and much more. There is something for everyone at Árbær Open Air Museum.