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Non wireless telephone lines. These are the network of fiber optic and metallic or copper phone lines you see up on the poles crossing the road.
www.gpsanywhere.net/cellular_glossary.html

land line: a telephone line that travels over terrestrial circuits; "a land line can be wire or fiber optics or microwave"
wordnet.princeton.edu/perl/webwn

A landline or main line is a telephone line which travels through a physical, land-based medium. This is distinguished from a mobile cellular line, where the medium used is the airwaves. A land line is also usually used to increase the security of communications, as it can not be intercepted by a receiver without physical access to the line. This does not, however, mean that a telephone company will not send the call over the air on some point in the journey.
en.wikipedia.org/wiki/Landline