I worked at an ISP back in the late 90s. We were in the same building as our backbone provider and they simply drilled a hole in the floor and dropped an Ethern

I worked at an ISP back in the late 90s. We were in the same building as our backbone provider and they simply drilled a hole in the floor and dropped an Ethernet cable down it for us to get our connection. We replaced our custom built dialup racks with something fancier and supported ISDN for the handful of customers who wanted it. The coming of DSL and cable internet was the writing on the wall to get out. The owners sold it to a larger ISP during a frothy period of mergers and acquisitions while the marketplace tidied itself up. There used to be dozens of ISPs you could choose from in a big market. Sigh.