The first step would be some research into how the cartographers of old practiced their skill. It would almost have to be allowable while on a boat, though I'd have to say only as a passenger on a boat. The height notion is the right path, which would make a boat with a crow's nest the ideal place for a cartographer. Thinking in the realm of skill progression, I think we're actually looking at two skills. Surveying and Cartography. Surveying would ultimately be the distance you can accurately observe and how accurate your measurement approximations are. Cartography would be your ability to accurately put your observations down on paper. I say this, because one wouldn't need high surveying if they only planned on making a map of their village for guests. Cartography would also be the skill you'd use when it came time to make copies of your maps. So, thinking about all this map stuff... An in-game map to view would be nice, but what if there was a skill and set of tools you could use to actually pin-point your location on said map? It would rely on the quality of the map (Cartographer's skills, paper quality) and your skill in reading maps (Navigation?). That's the only time I'd say a "pointer" should be on a map is if the player has the skill to work out their location. Again, the accuracy would depend on skill, the map, etc. But I think we're just getting more and more complicated.
