Technically it only requires an antenna that can listen on the LTE band (or even GSM). Trilaterating based on cell towers with a hackRF or other SDR is a fun exercise.
(Here in the States, they don't do that.
The best we get to have are crowd-sourced maps that are generally held behind someone else's lock and key.)
I'm in Canada, I don't think they broadcast their GPS coordinates. But most of their locations are publicly available, such as: https://www.ertyu.org/steven_nikkel/cancellsites.html?lat=51...
