[pct-l] Trail Mileage

[Gary Wright]

On Feb 7, 2008, at 4:39 PM, david booth wrote:
> you have really opened a can of worms here.
> I may be wrong but, IMHO, GPS distance measurements are 2D not 3D and
> don't take the up and downs into account.

I have no idea how a particular device computes the length of a route  
but the individual data points are 3d coordinates (latitude,  
longitude, altitude).  It would seem silly for a device to throw away  
the altitude information when computing distances.

Radar