[Tagging] Difference between barrier=embankment and man_made=embankment?

[Paul Allen]

On Wed, 29 May 2019 at 01:20, Joseph Eisenberg <joseph.eisenberg at gmail.com>
wrote:

> On github, Christoph mentioned that some of these features tagged
> barrier=embankment may be types of earthen fortifications, as found in
> Europe, eg earthen ramparts, earthworks or earth banks.
>
> > "Double/symmetric embankment not connected to some other primary feature
> like a road... something we in German call a 'Wall' "
>
> It could be translated "rampart" - "a large wall built round a town,
> castle, etc. to protect it"?
> Or "earthwork": "a raised area of earth made, especially in the past,
> for defence against enemy attack"
>

How the terms are used may vary from country to country.  OSM tags do not
necessarily
correspond closely to technical and/or common usage.  Meanings may differ
for
features like embankments depending upon context (railway embankment,
fortification,
levee, etc.).

>From what I've seen of scheduled monuments in Wales, the general usage
(other
than for a few scheduled railway embankments) is that an embankment is a
barrier
Earthworks are more complex features which may include embankments.
Sometimes
an embankment is described as a "linear earthwork."

Example:

A motte and bailey castle comprises a large conical or pyramidal mound of
soil or stone (the motte) surrounded by, or adjacent to, one or more
embanked enclosures (the bailey). Both may be surrounded by wet or dry
ditches and could be further strengthened with palisades, revetments,
and/or a tower on top of the motte.

Both the motte and the bailey are types of earthworks.

OT for this list: the rendering of an embankment implies that the drop on
one side is
significantly greater than the other.  This is often not the case.  It may
be true where
there is a ditch (barrier, not drainage) associated with the embankment.
Perhaps
embankments should be rendered with triangles on both sides of the line
because
if the ground on one side is significantly higher than the other it's often
a bank or a
slope or maybe even a cliff.  IMaybe we need a way of specifying equal or
unequal
drops.

For more examples of usage by UK heritage agencies, tell your favourite
search engine to
restrict itself to looking at the site ancientmonuments.uk (with google you
use
site:ancientmonuments.uk as a search term) and look for embankment, motte,
bailey,
earthworks, etc.

Yes, all fortification-type embankments are ramparts, but not all ramparts
are embankments.
Most people (if they use the term at all) associate "ramparts" with a stone
wall.  In my trawls
through the ancientmonuments site I don't recall rampart being used to
describe an
embankment (but I've only looked at a tiny fraction of the monuments and my
memory isn't
great these days).  Oh, and they're all walls, whatever the building
material, but in English
we wouldn't use "wall" without qualification, such as "castle wall" or
"curtain wall" and we
wouldn't generally use "wall" for an embankment.

-- 
Paul
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