The northern coast of the gulf is high and winding, with abundant small bays and skerries, but only a few large bays (Vyborg) and peninsulas (Hanko and Porkkalanniemi).
A costa norte do golfo é alta e sinuosa, con abundantes baías pequenas e arrecifes, pero só algunhas baías grandes (Vyborg) e penínsulas (Hanko e Porkkalanniemi).