I don't know how it is in other countries, but here in Poland we used to have 3 mobile operators, each one with their own cell towers, right now we have 4, but

I don't know how it is in other countries, but here in Poland we used to have 3 mobile operators, each one with their own cell towers, right now we have 4, but two of them have been bought by international comapnies (tmobile and orange).