[OSM-talk] definition of the main highway-tag

[David Lynch]

On Tue, Aug 4, 2009 at 20:13, Martin Koppenhoefer<dieterdreist at gmail.com> wrote:
> 2009/8/5 David Lynch <djlynch at gmail.com>:
>
>> That indicates that it's part of the Interstate system. Every highway
>> on the Interstate system is a motorway-class (high-speed and
>> grade-separated) road, but not every motorway-class road in the United
>> States is an Interstate. There is no equivalent to
>> http://en.wikipedia.org/wiki/File:Zeichen_330.svg to draw a clear line
>> between highway=motorway and highway=something else.
>
> As far as I have understood by reading English Wikipedia you have
> different classes (Freeway, Interstate, Numbered Highways) where at
> least Freeway and Interstate are motorways. Those seem to have
> unambiguous signs. May I suppose that I would not be allowed to ride
> my bike on any of these, even if the average speed on all lanes of the
> 405 in LA is 5 mph at rush hour?

"Freeway" is the general term in American English for what OSM would
tag highway=motorway (some people would also include toll=no; that was
one of the senses of the "free" part of the name when they first
opened.) Interstates are a subset of freeways. The majority of
centrally-maintained roads are numbered, and the majority of
unnumbered roads are locally maintained*. Interstates and U. S.
Highways have numbers and routes set by the federal government; other
centrally-maintained roads are numbered on a state-by-state basis and
states may even have more than one numbering system (Texas has about
four state-specific ones that I can think of off of the top of my
head, and 360 is a major urban road in three of them.) It's pretty
much anarchy, compared to Europe.

Generally, I would say that bicycles aren't a good idea, even when
they are allowed. The legal definition of a freeway varies from state
to state as do the restrictions that are in place.


* - Some rural counties use numbers instead of names, but a lot
dropped the practice in the last 15 years or so when a new law came
into effect about identifying locations for fire/medical/police
response.

-- 
David J. Lynch
djlynch at gmail.com