30th of april always is celebrated with fires and firecrackers. This tradition is in no way a christian celebration of spring. A practical reason to light a huge fire every little neighbourhood is to get rid of all waste from the garden (old christmas trees, twigs etc). The religious reason is to welcome spring and to scare all evil spirits away with the fire and firecrackers.
There were two fires in our little village. In the village nearby, along the lake there were three.
We went home early because of bedtime for the smaller ones. But we heard the firecrackers and fireworks all night.
A tradition that have dissapeared, is the way to scare the trolls and evil spirits away by dressing up in horryfieing masks. Particularly in Dala-Floda a village in the county were I live, this tradition is still alive. They call themselves Valborrar those ugly and scary figures.
Old picture of Valborrar. Source.
It's kind of equality magic, when you dress ugly and scary and making noises, to scare the natures entities away. Because when the season is changing those entities are tend to interact with people.
Picture taken today of Valborrar. Source
As I thought about this post. I was thinking of all our celebrations during the year that is not christian traditions. Walpurgis, Midsummer, Yule, and Easter. Typically for this county these traditions are stronger than in other parts of Sweden. If you click the link under the old picture you can read a well written article about those old but still living magic rituals. It is written in swedish but you can use some google translate or something if you don't understand the language.