Long Island, which forms the eastern shore of the Narrows, extends to the east-north-east a hundred and ten miles, enclosing between itself and the continent a broad sheet of water called Long Island Sound, that reaches nearly to Narragansett Bay.

The latter, being a fine anchorage, entered also into the British scheme of operations, as an essential feature in a coastwise maritime campaign.
Long Island Sound and the upper Bay of New York are connected by a crooked and difficult passage, known as the East River, eight or ten miles in length, and at that time nearly a mile wide[15] abreast the city of New York.

At the point where the East River joins New York Bay, the Hudson River, an estuary there nearly two miles wide, also enters from the north,--a circumstance which has procured for it the alternative name of the North River.

Near their confluence is Governor's Island, half a mile below the town, centrally situated to command the entrances to both.

Between the East and North rivers, with their general directions from north and east-north-east, is embraced a long strip of land gradually narrowing to the southward.