There are land lines and then there are land lines.
We stopped having phone service delivered through the copper pairs about 2013.
For a while, my folks and I both had phone service through the cable company. It was split off from the video cable and patched into the premise wiring.
What I have now is a Verizon home phone connect device. It's a dongle that picks up the cell signal and converts it to a POTS phone. It runs one phone that we use in conjunction with the security system. However, I could have just as easily plugged it into any phone jack in the house and used it to serve all the phones in the house.
