I'm not in the US, but the apartment building I live in is connected to so-called dark fiber that is run by the municipality. My understanding is that the fiber

I'm not in the US, but the apartment building I live in is connected to so-called dark fiber that is run by the municipality. My understanding is that the fiber cables are provided by the municipality and are then connected to a switch belonging to the ISP you choose. I can pick between 16 different ISPs with speeds up to 10 Gbit/s (both down and up).