Quick Dumb Question

[jmfargo]

If you were to go far back in time, GPS systems would be useless because there are no satellites, correct?

Is there a system, in use today, that can tell you your relative position on the face of the Earth without use of satellites, and not requiring any input from the user?

Comments

[jfargo.livejournal.com]

That's kind of what I'm thinking.

Either that or something focusing on the magnetic poles, (using magnetic north and some other semi-powerful magnetic source if such a thing exists) and triangulating where you are, but go back far enough and even that wouldn't work.