Another one from the vaults of my 1978 student tour of Europe...
We crossed the English Channel from Oostende to Dover, by a ferry that has since been discontinued. I do remember the ferry dock being near the big train station, and OSM supports this:
https://www.openstreetmap.org/#map=17/51.23083/2.92411 noting the "Transeuropa Ferries-Terminal" just north of "Station Oostende".
The nearest N route to this is N34, but alas it doesn't have a waypoint nearby. N34 uses a part of Leopold III-laan to go northeast from the Vuurkruisenplein roundabout, but then makes a right angle turn onto Ernest Feysplein (Google Maps shows this a lot better, as does Esri WorldStreetMap) and Leopold III-laan continues as N34g. N34g then turns onto Natienkaai and (if I'm reading Dutch Wikipedia correctly) ends at the train station, by which I imply the turnoff for the main parking lot where Natienskaai makes a right-angle turn.
Of course none of this is signed, but given the way Belgium signs its highways (mostly it doesn't), that's hardly a surprise.
I doubt we actually want to put N34g into the HB (not that I'd mind), but would it be feasible to put a waypoint on N34 at N34g, where Leopold III-laan intersects Ernest Feysplein?