# [Tagging] Feature Proposal - RFC - area:highway

john at jfeldredge.com john at jfeldredge.com
Thu May 12 12:58:46 BST 2011

```Also, sidewalks are not always directly next to the driving lanes.  There are sometimes grassy borders between the driving lanes and the sidewalk.  Typically, this is a meter or so, but can be wider.  On one street here in Nashville, Tennessee, USA, the sidewalk is about three meters to the side, and about two meters above the roadway, with occasional steps down to the roadway (the road ascends a steep hill on a diagonal).

-------Original Email-------
Subject :Re: [Tagging] Feature Proposal - RFC - area:highway
From  :mailto:simone.saviolo at gmail.com
Date  :Thu May 12 03:09:50 America/Chicago 2011

2011/5/11 Tobias Knerr <osm at tobias-knerr.de <mailto:osm at tobias-knerr.de> >

M∡rtin Koppenhoefer wrote:
>> If you follow the convention that each way should be drawn along the
>> center of the real-world feature, then the width of e.g. a sidewalk can
>> still be determined at any point along the road from just the single
>> outline area and the way position.
>
> no, if this would be possible there would be no sense at all to map
> areas. You can't see sidewalks as "just another lane", because they
> tend to be quite irregular in certain settings (unlike lanes which
> usually keep their width and have no corners and other weird points).

I don't think this contradicts my argument. Look at the cross-section of

| *  .  .  .  .    *  |

The vertical lines are road area outlines, the stars are sidewalk ways
and the dots are other "lanes".

If we make the assumption that each way marks the center of that "lane",
we can easily calculate the width of the two sidewalks at this
particular cut through the road: It's 2 times the width between the
sidewalk and the area outline.

How a cross-section of a road looks will of course vary a lot along the
road - lanes, including sidewalks, might change their width, disappear
entirely etc. But that isn't a problem as long as you can determine the

So your point is that we should use width=* to describe that? How about large sidewalks that get narrower were a bay of sort is reserved to cars (bus stops, parkings)? Should I break the way of the street into three parts, each with its own width?

Ciao,

Simone _______________________________________________
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