First, a clarification: there's no "NYC Island" named City Island. But City Island exists—a nautical-themed community in the Bronx, at the western end of Long Island Sound. It's part of NYC (Bronx County), connected by a single bridge.
City Island feels like a New England fishing village: seafood restaurants (Lobster Box, Artie's), antique shops, yacht clubs, and a maritime museum. It's a quiet escape within city limits—accessible by car, bus (Bx29), or seasonal ferry.