Talk:Tag:surface=gravel

Other potentially useful images:

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  Relatively loose relatively large gravel - but not too much.
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  Gravel sunken and compacted with dirt, forming relatively nice surface
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  Small loose gravel
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  Mix of sunken an loose gravel

Mateusz Konieczny (talk) 07:30, 13 March 2021 (UTC)

More examples

Gravel may often be used as a synonym of macadam according to this old discussion on related surface types.

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  Pure gravel
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  Loose and abundant gravel road in Czechia
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  Loose and abundant gravel road in Estonia
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  Somewhat loose gravel road in Iceland
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  Close up, for comparison with pebblestone
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  Gravel pedestrian paths in a courtyard in France
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  Gravel street in Brazil
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  Gravel-covered dirt road in Brazil

Fernando Trebien (talk) 18:40, 21 March 2021 (UTC)

Please make this more concise

I have seen "surface=gravel" on paths like this http://www.mountainbikers-paradise.com/tracks/lafatscher/fk/lafatscher29.jpg (the tour guide uses OSM http://www.mountainbikers-paradise.com/track/innsbruck/lafatscher) and where paths cross a scree, cant remember how many of those I let mistakenly drop. --Hungerburg (talk) 22:49, 15 April 2021 (UTC)

Note that short version of surface definition is at Key:surface, though if some parts are not needed and can be removed without losing something useful - feel free to make an edit Mateusz Konieczny (talk) 05:49, 16 April 2021 (UTC)

Perhaps, I worded my statement badly; I let drop the tag from the data; Eg. on Lafatscher Joch, otherwise all of the apex there would be surface=gravel now, while actually there is some gravel/scree on the way, but there are also rocks 10cm and more and a few 30-50cm steps of bare rock too. Would you agree, that gravel is a kind of cover for compacted? To me, all the pictures above seem to point at that. --Hungerburg (talk) 14:27, 16 April 2021 (UTC)

"Would you agree, that gravel is a kind of cover for compacted?" - sometimes amount of loose gravel is very large, sometimes there is only a bit of gravel and earth otherwise Mateusz Konieczny (talk) 18:25, 18 April 2021 (UTC)

I added a picture to the gallery that may or may not show a mountain path, I can see it! I'd never map there a surface=gravel, but in the data there are samples, and indeed, it is loose, as the definition does/did state.

Thinking about, how to disqualify the mountain path example - only this comes to mind: the gravel was not put there by humans. It is unpaved gravel, like surface=earth, while the other pictures might show paved gravel. --Hungerburg (talk) 19:10, 18 April 2021 (UTC)

I would say that such naturally occurring gravel can actually qualify for surface=grave (it is hopelessly broad anyway...) Mateusz Konieczny (talk) 20:09, 18 April 2021 (UTC)

Rocks of 10–50 cm fall above the gravel range by standard geotechnical scales: ISO 14688 and the Wentworth scale both place the gravel/cobble boundary at 63–64 mm. A path with exposed rock steps and 30–50 cm rock outcrops is surface=rock, not gravel. Proposing to document this upper boundary explicitly, see #Upper size limit below. julcnx (talk) 13:54, 4 May 2026 (UTC)

Upper size limit

The page acknowledges a "very wide meaning range" but sets no upper boundary. Standard geotechnical scales (ISO 14688, Wentworth) place the gravel/cobble boundary at 63–64 mm. A surface where loose fragments larger than this dominate is better described by surface=rock.

Proposed addition: state explicitly that the dominant-particle range for surface=gravel is approximately 2–63 mm, and that surface=fine_gravel covers the lower end (approximately 2–6 mm).

See: https://en.wikipedia.org/wiki/Gravel#Definition_and_properties

— julcnx (talk) 13:45, 4 May 2026 (UTC)

I agree with that and have been using that definition in my mapping since 2014, although larger rocks/ballast are very rare in my mapping region. --Fernando Trebien (talk) 14:12, 4 May 2026 (UTC)

Dominant character

The page does not address what happens when a surface has mixed-size material. The surface=compacted counterexample already encodes one direction: coarse gravel dominating = surface=gravel by community decision, even if some fines remain. The same principle applies in reverse: a bound and compacted matrix with a few scattered coarse or cobble-sized stones on top remains surface=compacted. Those pieces are incidental and do not override the character of the surface a wheel rides on.

Proposed addition: a short paragraph stating that the tag reflects the dominant character of the top surface, with both directions made explicit, cross-referencing the counterexample on surface=compacted.

— julcnx (talk) 13:45, 4 May 2026 (UTC)

Makes sense to me. --Fernando Trebien (talk) 14:13, 4 May 2026 (UTC)