There is the Nordic Hackerspaces mailing list hosted at Freelists. Archives are available publicly.
Staying in touch with CCC organizers
#coldnorth channel in CCC events rocket chat.
#coldnorth on Freenode
Hackeriet hangs out at #oslohackerspace on Freenode
Most if not all Finnish Hackerspaces can be reached on #hacklab.fi @ Freenode. Other infosec groups (HelSec, TurkuSec etc.) can be contacted through #citysec @ Freenode - a channel bridged to the CitySec Mattermost instance at https://citysec.disobey.fi/ (which also acts as another contact channel)
As there sadly is no current hackerspace in Reykjavik anymore, Iceland has no single natural endpoint for communication. They may have be contacted by poking different meetup groups and FB pages if possible. Let's try to get them join the mailing list.
Building a village or an assembly
Propaganda - Forming an appearance, helping people find us and marking our territory
What is this?
Cold North is a loosely affiliated assembly of mostly Nordic hackerspaces. All creatures are welcome, and don't forget to be excellent. :D