By which criteria do we determine whether or not to add cycling routes to the map?
Does global routes have to go through a local route network?
Does LCN/NCN/ICN routes have to be marked? What are the marking requirements for different network types?
Should the public organizations that have prepared the LCN/NCN/ICN routes have some kind of accreditation?
Does MTB routes must be away of dirt? What are the marking requirements for MTB routes?
Should the public organizations that have prepared the MTB routes have some kind of accreditation?
Same questions for hiking routes.
What is the current practice? I can’t find the answers to these questions in osm wiki.
One of the main principles is that the routes have to be marked. Otherwise, another mapper cannot verify the route. We do not map planned, proposed or routes that are only available in books.
To distinguish between a local, national or international cycling routes, you have to know “how far” the route takes you. A circular route around a town is clearly local, a GR-path that extends from one side of the country to the other is national, etc.
Where I live, MTB routes get special markings and here and there you will find maps with those routes. An example can be seen on this photo on Mapillary
It a regional (Pajottenland is a region) mountain bike network.