I associate May 1 with getting mashed in Helsinki as for many years I spent it in Finland, with amazing parties in the park for Vappu [0] the Spring Festival. It's a celebration of Spring, labour day, and also "education and industry" since people proudly wear their school colours, company badges and graduation caps. Quite an atmosphere!

[0] https://en.biginfinland.com/vappu-spring-fest-finland/