Travel
Grefsenkollen restaurant is located on a hill by the forest, roughly 25 minutes north of Oslo.
Taxi or public transport are the key alternatives.
A taxi ride with "Bolt" or "Yango", should cost in the region of 350 NOK.
The bus 56B towards "Grefsenkollen" from "Nydalen T", will take you directly to the venue. This is also an alternative for leaving the party. With one buss leaving grefsenkollen at 17:19.
https://goo.gl/maps/zaHacGmGEdHQxfBJA