Surface=fine_gravel - is it for loose gravel or duplicate of surface=compacted

hard to say based on this photo, that could be well-compacted or loose pile of moving fine gravel (visible tracks hint that it is relatively loose, but even with good compacted surface passage of many vehicles or heavy machinery can result in this)


this picture from surface=gravel page shows to me what fine_gravel (e.g. uncompacted fine gravel) often looks like (although often it is even deeper / more loose, i.e. more than one layer of it, so bicycle easily falls into it as is hard to cycle over):

to me this looks like gravel, although many of it looks like fine gravel there are also many pieces that seem to be bigger (than 8mm), 8mm are already at the upper end of what can be called “fine”

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That is correct, but when this happens the surface is no longer compacted but loose gravel. The road may well have a compacted base layer which is essential for the sustainability, but this one definitely has a loose surface layer. At the front left side you can see some corrugations (washboarding) which is a clear indication for a loose surface (notwithstanding if it had been compacted earlier and just become loose due to heavy traffic).

:+1: I would also call this a gravel road - there will be some fine gravel and even sand for sure but the majority is gravel up to some 50mm estimated.

Edit: Sorry, got the wrong pic, my comments were referring to the picture of Tamsa Road (and I believe @Mateusz_Konieczny did as well). Nevertheless the other pic shows a regular gravel surface as well - most of the stones are too big for fine gravel.

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Yeah I was referring more to looseness part of it; if it is indeed bigger than 8mm (I can’t really tell) then it would no longer be fine_gravel but indeed “regular” gravel. The other picture File:Tamsa.JPG - Wikimedia Commons is probably better example of looseness that both gravel and fine_gravel share (as opposed to compacted which is firm, not loose)

I do not see gravel there. The bigger pieces are pebblestone (rounded). The rest is a thin layer of fine-gravel over a compacted base.

FYI: Gravel and pebbles describe the same type of stone, naturally rounded by erosive processes whereas the correct term for sharp edges (artificially broken) material is “crushed stone”. Nevertheless "gravel’ is the common term used for all kinds of small stones of a size roughly in between 2 - 80 mm and any road or track with a surface of such stone, may it be rounded or sharp edged, compacted or loose is called a “gravel road” in common english. For more details have a look here.

A sample pic for pebbles:

A sample pic for gravel:

Any difference?

And here is a pic of a nicely compacted road:

which is called “gravel road” nevertheless.

And another pic of a road with loose gravel surface (as seen above)

Note to all though that while we might agree on ideal definitions on what is compacted and what is fine_gravel ideally, in reality tagging will always deviate to a degree from that because

  • the difference is somewhat fluent. E.g. old well-travelled fine gravel tracks may eventually turn into tracks where the gravel is not that loose anymore
  • for a long time, a different definition has been mentioned in the wiki, maybe in contradiction to other pages on the wiki (in other languages)
  • in colloquial language, in some regions or some languages, “gravel road” may be understood to be synonymous to any non-paved road

But it is good anyway if the wiki is clear on the distinction.


Ok, to avoid any doubt, I’ve just went outside and taken pictures. This is what I consider surface=fine_gravel:

One can (hopefully) see:

  • how bicycle wheel “falls into” loose fine gravel (if there is even more layers of fine gravel / i.e. deeper layer, cycling over it would be even more uncomfortable/hard)
  • hand for size comparison (although I’ve seen fine gravel which is somewhat bigger then the one in the picture, this is typical example in Croatia).

Can you upload it to Wikimedia Commons? I was planning to take picture like this to illustrate OSM Wiki (and for now at least weather in my area is not making easy to take illustrative pictures)

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I am rather trying to document actual tagging than design a new one in this case.

Very fine picture! Illustrates perfectly why one would want to differentiate between compacted and fine_gravel.


I took reference of - perhaps before @Mateusz_Konieczny worked to clear it up :slight_smile:

Curiously, what we here call “Kies” (fine-gravel in OSM speak), in construction means pebbles according to Kies – Wikipedia and what we here call “Schotter” (pebbles in OSM speak) in construction means crushed stone Schotter – Wikipedia

Curiously, what we here call “Kies” (fine-gravel in OSM speak), in construction means pebbles according to Kies – Wikipedia

have a look at this article again, the DIN 4022 distinguishes 3 size classes of gravel, fine medium and rough:

Kies (G/Gr) | Korngröße |

  • | - |
    Grobkies (gG/CGr) | 20,0–63,0 mm |
    Mittelkies (mG/MGr) | 6,3–20,0 mm |
    Feinkies (fG/FGr) | 2,0–6,3 mm |

and what we here call “Schotter” (pebbles in OSM speak) in construction means crushed stone Schotter – Wikipedia

also called “Splitt” or “gebrochener Kies” (the latter closes the circle)

This is one that I personally get stumped on from time to time and I’m glad we’re discussing it! I also wanted to grab a photo of what I’d consider compacted, as opposed to fine gravel.

Here’s my local rail trail (and a snake crossing it for scale). You can see there is fine gravel and sand in aggregate, forming a sturdy but pliable surface.

Sometimes this surface becomes eroded to the point where it may resemble fine gravel, and I think that can be confusing. If the compacted smoothness goes to horrible, is that now fine gravel?

Hi all
There are problems for OSM with the surface types fine_gravel, gravel and compacted. There are subtle shifts in the way the word gravel is understood by various speakers of English. Nearly all roads are compacted, a mix of particle sizes is typically graded and rolled. The larger particles leave gaps which are filled by smaller particles, the gaps between them are filled by sand and between them are dust. Later, as the road degrades, the dust and fine particles are lost to water and wind and the larger particles dominate the top layer. The road user sees loose gravel but underneath a thin layer of loose gravel is a compacted road.

Both the photos at fine_gravel are probably compacted, File:Finegravel0.jpg and File:DSC05537a-Feinschotterweg.jpg

I think there is little difference between loose gravel and compacted, maybe only a year’s wind and rain.

Some final notes. Gravel can refer to river gravel or crushed rock. Both compact with a range of particle sizes in the mix but angular crushed rock compacts better. Compacted requires the user to make a judgement below the surface where they cannot see, we are encouraged to tag with what can be ground truthed. Railway ballast, 40mm or bigger is a rare surface in my experience, it seems counter productive to use “gravel” for it. Users will continue to tag compacted surfaces as “gravel” regardless what is written here, shouldn’t the wiki document actual tagging rather than try to impose definitions.



Yes, I think this debate is really fruitless tbh. The definitions (past & present) include surface texture as well as subsurface composition (eg constructed road bases). All combinations are possible. Photos only show the surface, not what’s beneath. Contributors emphasise factors such as “looseness” which is yet another feature again, and one which quickly changes after rain and time since grading. The definitions of the existing categories (compacted, fine gravel and gravel) are all a bit of a mess and, not surprisingly, their application across the world is even messier. The more often that people change the wiki, the worse things get. Adding selective photos to override the textual descriptions doesn’t help either. I’d suggest that we accept that it’s all pretty vague and move onto other, more productive initiatives.

I wouldn’t call it fruitless at all. It’s important if you want to do bike routing with OSM data, for example. There’s a big difference between a lightly gravel-topped firm towpath and an unimproved trackbed of railway ballast, but both are sometimes described as “gravel”.


Yes, maybe just move on. But if we are going to make any progress, I think that good quality photos are essential. I may be guilty of “Adding selective photos to override the textual descriptions” but if so, it is unintentional, I have tried to illustrate what is in the text and any shifts in meaning are unintentional. More photos please.

In Sweden I have been using surface=fine_gravel as a less technical/less precise term of a gravel road with relatively smooth surface, while I’ve seen surface=compacted as a more technical and actually describing more then just the surface, but how the road is constructed. I generally use just “unpaved” though for roads I don’t have more precise local knowledge of. Other Swedish mappers often use “gravel” as the generic term for unpaved road, as in daily Swedish speak we say “gravel road” about basically anything that isn’t paved.

Anyway, lately I’m starting to regret some of my fine_gravel uses and would probably have used compacted instead. The surface of a maintained compacted road varies over the year, here during the spring new coarse gravel is put on, which then gradually is worked into the road to provide a harder more even surface.

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Yes, I ride a gravel bike. I fully agree that creating a separate tag for rail ballast is paramount. It’s what remains after that’s gone that’s a mess, given the poorly-differentiated mix of gravel, fine gravel and compacted in both the wikis and on the ground.