From Age of Titans
The Frost Sea is a bitterly cold and rough stretch of water, separating northern Seres from the land of Skalgar, and has a well-deserved reputation for piracy. Despite this and foul weather, many ships sailing from Karaport and other northern ports, make it quite accessible for those wishing to cross it, either on their way to Skalgar or other places further afield.
It is known to be patrolled by a great number of Skalgar longships who make frequent raids on the coastal regions of Cedronia, Sertoria and Ordovia.