Treacherous waters are oceanic regions that are dangerous for ships and other vessels to navigate. They may contain unpredictable tides, whirlpools, sea stacks, or jagged rocks just underneath the surface of the water. They may have frequent storms, fogs, or mists. Fictional treacherous waters may feature flotsam, shipwrecks or ship graveyards. There may be lighthouses nearby. They are home to shipwreck survivors, leviathans, and sharks.

When designing treacherous waters first consider why they are so dangerous. There may be natural or unnatural reasons for why this area is treacherous to cross. Fictional treacherous waters often contain secret routes that allow vessels to get through safely, but these routes may only be known to smugglers, pirates, or experienced sailors (unless someone made a map…).

What sea creatures inhabit your treacherous waters?