Answer: icefree

AnswerCrossword Clue
ICEFREENavigable year-round
ICEFREEEasy to navigate, in a way
ICEFREELike some northern ports
ICEFREELike Murmansk's harbor
ICEFREEClear, as winter windshields
ICEFREENavigable in winter, say
ICEFREEWithout frost
ICEFREESome winter ports
ICEFREEUnfrozen as a harbor
ICEFREELike some winter ponds