For everyone who loves surströmming, the third Thursday in August is something special.
Surströmming has a very strong aroma and taste.
Many who have not tasted it before think it smells and tastes bad.
But there are also many people who love to eat sour strömming.
It is most popular in northern Sweden.
In the clip above, you can see how you can eat the beloved and hated fish - Boo Dahlin's way.