Plan was, to ride a bicycle to a destination some 50km away, go there for a walk ; in setting the route found that several errors had been introduced in the process of further improving OSM ; amended, based on aerial imagery and in many instances local knowledge.
First and foremost, change set comments are of course the correct way to alert the mappers concerned, and they’re used for that purpose ; here the question is on a different aspect :
It would be helpful if there were a way to download a ‘fresh’, ‘overnight’ map fragment.
Does such an option exist, and how can a mildly active mapper access such an extract service, please?
In this case the fragment would measure 50km west>east and 15km south>north, to load onto an Oregon700, so that turn instructions will be based on the updated map rather than send me on detours where (although undoubtedly well-intended but) unfortunately careless* and/or ill-considered** mapping introduced virtual no-go areas.
Here below the starred terms used are clarified, including some of the issues which cause those detours, it may be disregarded for the purpose of pointing to a source of ‘fresh’ map fragments.
- In an above paragraph, ‘careless’ is used to indicate that the mapper did not, before committing the change, sit back to take a look at the consequences of adding for example ‘vehicle=no’ or ‘bicycle=use_sidepath’ (careless, as it seems obvious that in order to take that path the path needs to be on the map, in this case it wasn’t) or added a separate cycle track yet overlooked connections to side streets , or added a one-way=yes or ‘access:vehicle=no’ restriction either based on an incomplete Mapillary traffic sign recognition or a temporary sign where closure is due to a local one-day event or long since completed road works.
** Ill-considered is where one mapper added a way, drew it to connect to a cross-road which was later, by another mapper, tagged as bicycle=no (the cross road is a motorway link, it concerns a cycle path which continues after the crossing, and actually, the ‘motorway regulations end’ sign is placed before one reaches the cycleway - hence it is no longer a motorway at that point, or the instance where a prolific mapper correctly added a short (10m?) stretch where, once a separate cycle-crossing had been built, the still visible and blocked cycle lane ought not to be used, but in doing so also marked a much longer stretch of that way as cycle-lane=no, even though a cycle lane does exist; the effect is that one who relies on OSM needlessly crosses a fairly busy road twice.
While I’m at it : another cause of routing errors are ‘wenslijnen’ (Flemish for ‘wish lines’), where cycleways which will undoubtedly be built at some point in the far or near future (but so far haven’t entered the detailed planning process) are already added as a cycle route relation (rationale : if -at some point in the futute- someone spots and draws a way, it will automagically be tagged as ‘Fiets-o-strade’ (Flemish word for a purpose built nice 'n straight cycle highway, often alongside railway tracks - what could be nicer than mapping cycling infrastructure from the comfort of a train? (What would be nicer is not arriving at a spot where there is no usable highway ; this is caused by route planners, in selecting the low traffic or scenic option, look for marked cycle routes, and as the wenslijnen are marked as cycle route the non-existent way is included in the plan.