Aura is a type of blue cheese produced in Äänekoski, Finland. Aura is made of cow's milk and takes its name from the Aura river, which runs through the city of Turku. The cheese is available in two varieties. The regular variety is aged for 6 weeks whereas the stronger 'Aura Gold' variety is aged for 12 weeks. It is marketed in the United States under the name Midnight Blue.