Zip Code Distance?

[+diegodooleys]

I just have a question about the distances listed when one queries a zip code on geocahing.com. Where are the distances measured from? The P.O. with that zip code?

 

Thanks,

DiegoDooleys

[+Lil Devil]

Already asked and answered in another thread

[+trainlove]

Zipcode locations come from the Tiger Census database as used by the US Postal Service. They are sort of arbitrary and not the geographic center of anything physical.

 

Now even more frustating is that the same Tiger Census database is what's used for most older mapping software. And there one can see that the database has little to do with reality. Most roads are some 100 feet off from where ALL GPSr's say they are.

 

I have no idea why that data is so unreliable. But I know why it's so prevalent, the database is free for the asking. This is one reason that Garmin's cost more than Magellan's, Magellan goes with the free data, while Garmin has paid for some more recent and much more correct data.