Oh. I found it. It was Florida rail. I'll update the numbers with more accurately sourced ones. It should be 260000 km according to Wikipedia, although statistica lists 149000km (still the largest in the world, but significantly less). I wonder if the Wikipedia number is before a bunch of rails were destroyed. Basically that would be our high score, but really the high speed rail should be the goal of which we basically have none.

Statistica also lists the European Union, so not all of Europe, at 220000 km in 1990 (and declining since then, but who isn't). Dunno where Florida rail got their numbers but I should know better to trust anything coming out of that state.