Interesting, didn't know. It felt like high-tech to me, anyway, since I had not seen or heard of train ferries before, although I did know about ferries that can take cars (automobiles) on board. Been on one such ferry in Goa, and my parents had been on some while visiting the US and Canada, I forget in which city.
As the Wikipedia article says, there are very few routes left in Europe, although there used to be a lot.
https://en.wikipedia.org/wiki/Train_ferry