斯默根，瑞典 Smögen, Sweden (© Martin Wahlborg/Getty Images Plus)

斯默根，瑞典 Smögen, Sweden (© Martin Wahlborg/Getty Images Plus)

It's surströmming time

The historic wooden pier of Smögen, Sweden will be busy—and pungent—today. The third Thursday in August means one thing: surströmming season has arrived and all over Sweden, brave residents stand at the ready with can-openers in hand. If you've never taken part in a surströmmingsskiva, the Swedish word for this particular event, you're going to need a bucket of water, some side dishes, and a strong constitution.

In April and May, freshly caught herring from the Baltic Sea is quickly brined in just enough salt to keep the fish from rotting. In July, the rapidly fermenting fish is canned and then, come this day every summer, the cans are opened—outdoors and often submerged in a bucket of water to reduce the smell—and eaten with flat bread, potatoes, and usually a chaser of strong alcohol or beer. Some say sour herring, aka surströmming, is one of the most putrid smelling foods on Earth. Others say it's delicious.