Distortion
Distortion is most famous festival happening in Copenhagen during summer.
Aalborg Carnival
Aalborg is a bit far from Copenhagen, but it could be worth it to go if you want a very local activity to do and you like electronic music.
It’s a one day carnival that consists of going around the city with loud electronic music (mostly techno), disguised and (little bit) drunk.
Roskilde Festival
It’s one of the most famous festival in Denmark happening during the summer: