May 1 in Scandinavia

Image: Mad John
Terri Mapes from About.com recently wrote an article about celebrating Labour Day in Scandinavian Countries:
Labour Day in Scandinavia (also called May Day) takes place on May 1 every year, following Walpurgis Night on April 30. Labour Day in Scandinavia is a celebrated public holiday - and quite visible. Visitors can see lots of festivities, parades, and other celebrations every year on the first of May in Scandinavia when locals celebrate Labour Day. You’ll find special events in every city on this day.
Read more on About.com: Scandinavia Travel
I can add that in Finland there is a holiday called “Vappu”, it’s mostly dedicated to persons graduated to some high school level, and whole Suomi selebrating this day with special for this day Sima (light alcoholic beverage) Tippaleipä (some kind of cake similar to Funnel cake), donuts and potato salad. People wearing white student caps everywhere and funny masks on parties.

