The Seahorse Restaurant 65 Marsh Rd, Groton, CT06340 The Seahorse has a great atmoshphere to match the service and seafood available inside. There's ample seating for…More large groups -- up to 100 people. The menu has three different types of chowder, oysters, mussels, clams, wings, calamari and shrimp cocktail, to name just a few of the menu options. In business for more than 25 years, the Seahorse offers plenty of deals and promotions. Order up a drink and pub snack at the impressive bar.