[pct-l] gps / gis for pct path?

[brick at fastpack.com (Brick Robbins)]

At 06:43 PM 12/29/03, AsABat wrote:
>I think he's looking for a GIS shape file rather than just GPS coordinates.
>I haven't seen one, but would expect the feds have it. Not sure how you go
>about getting one, though.

One of the problems of GPS mapping of the PCT is that the topographic maps 
are not accurate. Because of this, the guidebook authors drew the trail 
location in the guidebooks relative to the contour lines, not the correct 
lat/long.

For this reason GPS maps of the trail don't track the lines on the map.

In some areas the contour lines show the geographic features as much as 
0.5-1.0 miles off the actual lat/long position, so it is a bit 
disconcerting to see your track take you over a peak instead of the pass.

Quite a bit of GPS mapping of the PCT was done in Lassen National Forest (I 
think) a few years back, and that project showed this problem in spades.

--
Brick Robbins
I'm not tense, just terribly, terribly alert.