Not sure if this is a funny quirk that was intended, but STC and CC share a single zone/tile, being sister-islets.
The problem is.. STC puts you on the east side of that zone (despite being the western island) and if you sail eastwards to CC you end up on the west side of the zone - despite it being the eastern island.
Obviously this could probably be waived by simply saying the 'top' of the in-game map isn't north, so I'm not entirely sure if this is actually a bug.
Furthermore, each of these islands has two docks - one at the entrance and 'exit' of the mini-dungeons, and the secondary docks don't seem to link anywhere, or actually be usable, despite opening the boarding prompt.