This book in the series of Citybooks focuses on businesses, NPCs, and scenarios with a distinctly nautical theme.
From the front cover:
A game-master's aid for all role-playing systems...22 seaside businesses, over 70 fully developed non-player personalities, and more than 60 scenarios for use with any role-playing system.
GAMES: Middle Passage, Elfquest, Victorian Adventure. SUPPLEMENTS: Advanced Dungeons & Dragons Monster Manual
Schatten über Travias Haus (DSA); Die Insel der Risso (DSA); etc.