Ghosts of Saltmarsh is a collection of seven adventures for Dungeons & Dragons, set in and around the coastal town of Saltmarsh. It provides a detailed overview of the area, rules for ships, sailing, naval combat, and underwater exploration, as well as new monsters, magic items, and backgrounds. The book is well-written and well-illustrated, and encourages DMs to use the tools and tables provided to create their own adventures. It is a great resource for DMs and players who want to explore the nautical side of D&D, with rules for ships, sailing, naval combat, and underwater exploration.