Enjoying the countryside and coast in Norway is defined by Law,
here’s a link to the Norwegian Governments English translation
A couple of extracts…
§ 7. (Landing and mooring boats)
Any person travelling on water has the right to land a boat on a beach in an uncultivated area for a short period of time. It is not permitted to make use of a quay or jetty without the owner’s or user’s permission. Other mooring devices (rings, bolts, etc.) in uncultivated areas may not be used if this has been prohibited by the owner or user. The owner or user may nevertheless not oppose the use of such mooring devices for a short period of time if this can take place without unduly hindering the owner or user.
§ 9. (Picnicking and camping)
It is not permitted to use sites on cultivated land for picnicking, sunbathing, staying overnight or the like without the permission of the owner or user.
In uncultivated areas, it is not permitted to use sites for purposes such as mentioned in the preceding paragraph if this unduly hinders or inconveniences others. Picnicking and camping must not take place if this may cause significant damage to young forest or to regenerating forest. A tent must not be pitched so close to an inhabited house (cabin) that it disturbs the occupants, and in any case no closer than 150 metres. However, the rules on the distance from habitation do not apply in an area that has been specifically designated for camping.
Camping or another form of stay is not permitted for more than two days at a time without the permission of the owner or user. Permission for a longer stay is nevertheless not required in mountain areas or in areas distant from habitation, unless it must be expected that the stay may cause significant damage or inconvenience.
Immediately before and during the hunting season for wild reindeer, the Ministry may prohibit or regulate camping that may cause inconvenience for such hunting.
Camping and other forms of access must take place at the person’s own risk as regards damage that animals may cause to persons, tents or other property.
Without doubt, there is great willingness to help in Norway, people are friendly and make it easy to ask. If you are asking for permission to park or to camp, if they cannot give you permission they will always give you an alternative, which is likely to be better.