The North Atlantic Tracks connect Northern Europe to North America. To enter/exit NATs over North America, the North American Routes (NARs) are used.
Questions: What about the European side? What are the rules to enter/exit NATs? What airways must be flown? Can I find the official information written anywhere?
Note: Ideally I would like to find a list of routes (directs?) that suggests the pair of waypoints linking the generic NAT and the european airways system. In the past North Atlantic European Routing Scheme (NERS) was used but nowadays it appears they have been dismissed.