New Hampshire State Boundary with Marine Jurisdiction

This feature layer represents the complete legal boundary of the State of New Hampshire, encompassing its four terrestrial borders with the states of Maine, Vermont, and the Commonwealth of Massachusetts, as well as its marine jurisdiction extending into the Atlantic Ocean. The offshore component includes the state's full marginal sea — three nautical miles in breadth, measured from the coastal baseline drawn in conformity with the treaties to which the United States is a party. The layer's geometry and attributes are derived directly from New Hampshire Revised Statutes Annotated (RSA), Title I – The State and Its Government, Chapter 1 – State Boundaries (RSA 1:1 through 1:19), which constitutes the foundational legal authority for all state boundary definitions.