The central river that runs through the middle of Limani carries a current strong enough to sweep even the largest of vessels out to open sea. Despite that fact, the Crown's Canal is frequently traversed, ships of all shapes and sizes streaming colourful flags as they move upriver toward the city's heart. This feat can be accomplished due to the work of the city's Hydromancers; water mages stationed around the canal day and night who quell the current to permit access into the city...for those who have the proper paperwork, of course.
Hydromancers work under the esteemed Minister of Defense, and can just as easily remove a ship from their waters as they can allow safe passage.