--- Begin Forwarded Message ---
Date: Tue, 14 Mar 2000 10:41:54 -0700
From: "Sanderson, Dale" <[log in to unmask]>
Subject: RE: Area codes by county
Sender: "Sanderson, Dale" <[log in to unmask]>



I too have looked for detailed info on area code boundaries, and been unable
to find it.  That's because, from what I've been told, the boundaries are
not truly geographical.  Instead, they're based on exchanges and prefixes,
and those can be intermingled in a given geographic area.  So those lines
you see on an area code map are to be considered approximate boundaries
only.  If you were to zoom in too close, you'd have to take into account the
specific phone number(s) that serve each individual property.  In other
words, the best way to determine precise area code boundaries is not with a
map, but with a list of exchanges and their locations.

The North American Numbering Plan Assc. website (www.nanpa.com) is a good
resource for area code info.  The planning letters available in pdf format
from that site often contain fairly detailed maps showing the boundaries of
new area code splits and overlays.  But I'm not aware of any maps of that
level of detail showing existing area code boundaries.

Dale Sanderson
Cartographics Manager
Creative Publishing Group, US WEST Dex
http://www.geocities.com/mapguy_denver
(Website completely reformatted for Y2K)

> Virtually every computer in the world is running the Macintosh operating
> system.  Unfortunately, the majority of them happen to be running the
> Windows version of it.
>
>
> ----------
>      I have a reader seeking telephone area codes mapped by county. He has
>      only found a few sites on the web, usually associated with university
>      sites. He needs this for Pennsylvania, Massachusetts and New Jersey.
>
>      No, the individual telephone book maps are not adequate...
>
>      Thanks for any clues out there!
>
>      Alice Hudson
>      Map Division, NYPL
>      [log in to unmask]
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