Wentworth by the Sea Marina | 115 followers on LinkedIn. 175 Slip Resort Marina located in New Castle, New Hampshire directly on the Atlantic Ocean. We offer seasonal as well as transient dockage to vessels up to 250' with power requirements up to 3 phase 100 amp service. We also offer full concierge service from the moment you make a reservation, car rentals, event tickets, dinner reservations, we do it all.