the EuroVelo working group started its work on the premises that Nadjita’s proposal for taggign segments and stages would be a good basis, and that the examples from EuroVelo would help consolidate the proposal. Here we go, with the example of EV17 that raises a couple of questions:
how do we tag and number daily sections? per country or globally? using which tag on which object? This question seems related to the question of keeping or removing national relations in the structure of EV relations.
how do we number daily section in branches? Although the EuroVelo charter discourages branches, it seems that we have two in EV17 (around Geneva Lake and Camargue) and that the GPX file distributed by ECF does not help.
The problem with numbering I think is difficultly solvable is that a same stage relation can be part of several route relations. I.e. a stage part of ViaRhôna and EV17 should have two different numberings for the two different relations. Maybe it’s not an information that useful, as numbering can be retrieved by reusers by the ordering in the route relation.
In the EuroVelo database, we don’t use numbering. We just order the daily sections geographically, depending on their start and end points. And indeed, the same stage on OSM can be part of a number of relations - including being part of several EuroVelo routes, as many of them have shared sections.
Is the numbering essential on OSM? What would be the consequences of using from=* and to=* tags instead of numbering? Is there anything that would become more complex if we did that?
I try to analyze this kind of question along four axes: contributing, QA, indexing, rendering. I don’t think that stage numbers are currently used for rendering and indexing. As for contributing and QA, here are two pictures that illustrate why I currently like numbers in the names of sections:
Here, the relation browser on the OSM web site. Apparently a contributor has made ordering mistakes.
But I guess that tools can be improved to provide alternative solutions. If sections numbers do not exist for you, they have no real existence and should not be in OSM I suppose.
If there’s consensus to use numbering of daily sections or stages then I would prefer new numbering for every branch. Have a look at EV17 - would you divide the ViaRhôna part into the same number of stages as the R1 part from Andermatt to Genéve? I wouldn’t do that.
About discouraging branches, what about doing EV15 next?
There are two branches from Lake Constance to Basel right and left of the Rhine, only one in the city of Basel, two branches right and left of the rhine from Basel just to the border of the Netherlands. The branch on the right side of the Rhine is sometimes interrupted and seems to end a bit unmotivated (or just not developed) at Spijk.
If we number daily sections and do a renumbering for segments, I would prefer only to restart the numbering at borders if there is the begin/end of a segment. I would not restart the numbering of the east segment between Basel and Karlsruhe at the French-German border near Neuburg am Rhein.
I am 100% aware that EuroVelo does not equal USBRS. However, USBRS (in OSM, now at version 2.3.5 to reflect Autumn 2023 approvals by AASHTO, USA’s national cycleway network numbering authority), after “igniting” (and burning since) with correct routes in OSM since 1.0 (mid-2013) does have carefully-wrought, simply-explained ways to break up continental routes. We do so “state by state” which I know hasn’t really a direct equivalent for EU (and it isn’t “stages,” and I understand what those are w.r.t. bike routes) and so have naming conventions in our USBRS wiki (and regards to name=* and ref=* tags). These are regular, sensible and render excellently in OpenCycleMap, cyclosm, waymarkedtrails and other bicycle renderers.
Part of this is a result of the nuts and bolts of how we’ve built it, but it does streamline the semantics as it streamlines the syntax. And it is (somewhat) succinctly described in our wiki.
Keep at it. EuroVelo is a wonderful thing, USBRS is a wonderful thing (and only partially completed, maybe 40%, but it is planned out, has good rules, numbering protocols, architects working on things, established process with our state departments of transportation and national network numbering process). They are in effect similar or even same things, but they most certainly can allow themselves to be tagged and organized in ways that make sense “local to them.”
USBRS uses one super-relation for each route if there are more than one jurisdictional (statewide) route. This means that (according to the “corridor plan” from the 2000s) routes can and do “sprout” in a patchwork fashion, but growth has been steady, measured in decades of time to build them (>30000 km now, growing to 80000 km or so, on par with EuroVelo’s ~90000 upper edges).
These systems have evolved over decades in both the real world and in OSM. Please refactor them with great care.
