Chepiwanoxet is a neighborhood in Warwick, Rhode Island, with an island peninsula in Greenwich Bay, an arm of Narragansett Bay. The neighborhood straddles the Amtrak railroad lines, which lies just east of and parallel to the Post Road (US Route 1). Its boundaries are Neptune Street to the North, Alger Avenue to the South, Post Road to the West, and Greenwich Bay to the East. Chepiwanoxet Way, an underpass beneath the Amtrak lines, now serves as the only street access in and out of the neighborhood.