I second the recommendation of Bahn.de. For like two decades now it has provided a way to search train schedules across Europe when the national rail companies didn’t bother to provide their own accessible interface.
I was thoroughly confused trying to book a French train yesterday when I realized that the regular SNCF website only lets you browse train schedules.
You had to lookup the schedule on another website (oui.sncf) to do the booking.
Then Iberia airlines kept showing a different date at the top menubar, which was a day before what I was actually booking. Thankfully the date in the body was correct.
Bahn.de is remarkable. You can search for Paris->Beijing if you want(202h with one change or 173h with three changes). Or you can look up the train schedule of a remote Scotish villages.
Off-topic, I remember reading about the history of the online Bahn schedule lookup, it apparently started with a guy, not affiliated with them, who put the contents of the Bahn's CD-ROM timetable online. IIRC that was 1998.
"If we are at step 4 for a long time, I'm probably personally at the machine and doing some tinkering.". I love that there's no separation between a developer and productive system.
You can book some trips that go through Germany but don't actually start or end there (e.g., Amsterdam-Göteborg).
Conversely, there are some trips that are best booked online on the web site of the national railway of a third country. For example, the site of the NMBS (Belgian Railways)[0] knows about some Dutch fare reduction cards that the DB (Germany) doesn't know about, while it also knows about more German stations than the NS (Netherlands) does, so some (admittedly fairly obscure) tickets from the Netherlands to Germany can only be bought online on their site.
