Fastelavn is a carnival tradition primarily celebrated in Denmark, although it is also observed in several Northern European countries, including Norway, Sweden, Iceland, Greenland, Finland, Estonia, and the Faroe Islands. This festivity occurs on February 15 and is linked to the Roman Catholic tradition of Carnival, taking place before Lent. Customs include children dressing in costumes and going door-to-door to collect treats while singing the Fastelavn song, which is about sweet buns known as 'Fastelavnsboller.' Another popular activity is ‘slå katten af tønden’ (hit the cat out of the barrel), similar to a piñata, which takes place after the church service on Shrove Sunday. The celebration has distinctive characteristics in each country, reflecting local traditions while maintaining a shared heritage.