Mapping bouldering routes

Hi all!

After a mapping party near Fontainebleau (a famous climbing area in France) I have started mapping one of the many local crags (there are about 200). More precisely, I have focused on what they call circuits : routes across the forest where you walk from one numbered problem to the next. For instance the yellow circuit at Maincourt has 30 numbered problems whose difficulty range from 1 to 3+.

I have failed to find examples of such “circuits” in OSM and I have two questions:

  • what is the exact meaning of climbing=boulder? is it “this is a boulder”? or “this is a climbing route (a problem) on a boulder?”

  • how would you map “circuits”? I went for a relation with type=route, route=bouldering, and one member for each problem. Does it feel right to you?

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First a caveat - I’m not a climber or a boulderer (is that even a word?). I’m just trying to make sense of the way that OSM has recorded these features on a map.

Usage in the UK suggests the former rather than the latter. This overpass query shows no non-closed ways with that tagging.

At least in the UK, I don’t think anyone has, so your proposal seems as good as any, but I’d definitely investigate taginfo for suitable values.

For what it’s worth, on the map that I’ve created that shows this stuff I’ve tried to separate “sport climbing” (e.g. indoor climbing walls) from natural boulders also used for bouldering. See here with the former on the left and the latter on the right. Regular bits of rock with no sport association look like this.

If it’s one path or a few paths along the numbered boulders, how about (existing tags) leisure=track & sport=climbing & climbing=boulder ?

If the wood has many paths and you have to follow signs to get to the next boulder, a route relation seems appropriate.
A route without ways does not feel right to me.
The ways would be paths or footways I think.
Each boulder would be a node with its own tags, including ref=boulder number
type=route & route=climbing & climbing=boulder seems right to me.
route=climbing is new, I think, but I didn’t look at taginfo.

Not a Boulderer here neither, but what I got told and witnessed on site, a Boulder is something people make up from looking at a wall, spend some time on it, solve it or not, and then it is gone, ephemeral, so to say?

I am a climber, and have done some bouldering.

They are not ephemeral. They are often documented in guidebooks and online, e.g.:

Since many climbing routes are vertical, it makes sense to map them as nodes. The alternative is to have a way with a node at the top and one at the bottom of the route both with the same lat, long, but perhaps different ele=* values.

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I think the issue was a route through the wood, visiting a series of boulders. Such a route needs ways, I think, while the individual boulder problems would be best mapped as nodes.

(The issue reminds me of the Stations of the Cross: a series of wayside shrines. I decided not to use a route relation to map this, because the route is very obvious, no-one would need a router for it; the route would need to be for different transports at the same time; and routes are not shown on regular maps. The individual Stations as POIs are enough.)

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Are there designated, maybe even waymarked / signposted paths between the boulders that tell you how to get from one problem to the next?

Is the forest open to the public and people who aren’t bouldering would just think of them as normal hiking paths, or is the purpose of the paths (only) to link the problems?

Are the problems fairly close together, like holes in a golf course, or further apart?


what is the exact meaning of climbing=boulder? is it “this is a boulder”? or “this is a climbing route (a problem) on a boulder?”

in some occasions this is for facilities set up for “bouldering” (climbing without protection thus without going higher than a few meters, typically 4m), e.g.

in other occasions these describe natural features apparently suitable for bouldering, e.g.

Not sure if it is also used to describe a boulder (big stone, not attached) where you can climb, didn’t see such.

Generally I would see it as a specification of climbing, i.e. a subtype of sport=climbing, although other values of the “climbing” key suggest the key also used with different meaning (parts of a route):

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I can’t say for all crags in general, but in Fontainebleau the forest is state-owned and open to the public except for protected areas. There are some paths, but not signposted with regard to these “circuits”. Moreover, there often are no clear paths between blocks, climbers just walk across the forest from one block to the next; they resort to real paths when the blocks are significantly far apart, which happens sometimes.

All in all, I don’t think that paths (ways) play a significant role in “circuits”. I’d relate this to the routes that are created with cairns in rocky areas: you follow a route without following a path.

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So you rather favor “this is a bouldering problem” over “this is a boulder”, right? If yes, maybe we need to adjust the wiki to clarify this.

I am not sure about “this is a boulder” in some instances, but generally, when it is a subtag of sport=climbing, it is not restricted to bouldering problems, it can also be in other ways related to bouldering, e.g. a shop selling equiment, or a sports hall dedicated to bouldering, or an association dedicated to boulding, in this reading, it is a property (like an adjective in language) and you have to look at the “main” tag to see what it is

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How do people know what the next boulder is and how to get there?
Is there a particular order in which people have to clear the boulders?
Do they have e.g. maps showing where the boulders are and which difficulty these have?
Do people get a list somewhere with e.g. easy, challenging, expert boulder sets?
Do people make up their own list and route?

Trying to figure out if there is any fixed route at all. So far, it’s not even a pitch, because it’s a free access area for others as well.

PS. I am sure the individual boulders deserve to be mapped. Then boulder maps, selections and lists can be made of the area from OSM.

Please don’t use leisure=track for this, they don’t sound remotely track-like.


They just know :slight_smile: More seriously, either they are equipped with a map or a guide, or they scan the surroundings for the next route/problem (which sometimes is on another side of the same boulder).

The routes/problems are often numbered. But of course nobody prevents you from skipping a number that you have been unable to clear.

Firstly, maybe I was not clear about this: there are arrows and numbers painted on the stone, and sometimes (rarely) on trees to help you locate the next boulder. Then you have maps, gathered in guides that give all the details. Today, websites such as and are taking over.

Routes are designed by people. I mean, it is more individual than hiking routes: you can often find the name of the person who has designed and painted the route. Still, they are as normalized, known and documented as a GR.


Have a look at how this area has been mapped.

You don’t necessarily need a relation, you could just map the boulder as natural=stone sport=climbing climbing=boulder (or climbing:boulder=yes) and put the number into ref.

This mirrors, for example, how golf courses are mapped (with golf=hole and the number in ref).

Disclaimer, I’m only familiar with ‘bouldering’ indoors. Just reporting what I see on Taginfo and Overpass.

I would argue that this is a good use of relation:site – this is a group of related, numbered objects, but not otherwise strongly connected by a route or another geometry.

Now, the fact that site relations are poorly supported by the existing code stack (Nominatim included, IIRC) is a different issue… :pensive:

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Chicken and egg, I would say. The objects define the route, and they are connected by it. Same as cairns defining a route in a mountainous area, and same as a way (if you push the reasoning to its limits): the geometry is defined in part by the points, in part by interpolation and extrapolation.

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This question has interesting parallels to a recent discussion about how to map exactly such hiking routes, that are best described as a series of waypoints but without an obvious path between them.

(No clear solution has been found so far)

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The interesting difference is that such a hiking route defines the waypoints and the order in which to pass them, just not the exact itinerary between each two “mandatory” waypoints, while this boulder forest does not prescribe which of the waypoints to visit. If there are clear routes indicated by signs such as “John’s adventure” guiding climbers along John’s pick of the boulders, then you have an OSM-route. If the exact path between some numbered boulders on John’s Adventure is not indicated, just the general direction, then you have a comparable situation to the “find your own path” situation.

If there are cairns on this way, which are a type of waymarks, that would make it a regular route, telling the user where to walk.

If the boulders all had arrows pointing to the adjacent boulders, that would make it a Node Network. We have discussed how this could be mapped as a Node Network, even if the exact itineraries between the Nodes are not prescribed. The Node2Node route relations would then simply contain no ways. Then you have the Network, with DIY itineraries in between. Node Network routing applications could learn how to handle the unknown Node2Node routes, e.g. by connecting the Nodes visually with vaguish meander lines, which act as stubs for the missing ways.
Which could be a generic solution for other situations, e.g. when a route has been interrupted without a known alternative (happens a lot!): the traveler has to find a connection at the spot, and the planner app shows it when planning the trip.

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This is a question of climbing ethics. Nobody will physically stop you from skipping a numbered problem, but whether you have then completed the circuit will be brought into question.

Think of it as a marathon route. It might be physically possible to take a shortcut, but do you then have a claim to having run the route?