Surströmming is the word for "fermented herring", and it's been a part of traditional (and smelly) Swedish cuisine for centuries. Most languages find one word for "herring" is sufficient, but in Sweden there's a difference between herring caught south of the Kalmar Strait, which are sill, and those caught in the Baltic north of Kalmar, which are strömming. For many people in Sweden it's a tradition to eat fermented herring every summer