I recently found a Nordisk Faergefart A/S Summer time-table from 1972, which I collected on my travels. The "VIS" started life as "SYDFYN" running a service between Faaborg (Denmark) and Gelting-Mole (Germany). She was a RO/RO ferry that could take 60 cars and 500 passengers.
I remember it as a pleasant low-key trip, which, the time-table reminds me, took two hours and ten minutes.
It cost £0.55 one way in those days.
I remember that the captain announced that anyone who wanted to exchange Kroner for Deutschmarks should proceed to the bridge and he would transact business; the view from there, over a calm Ostsee? was great.
Gelting-Mole seemed like the middle of nowhere.