It is directly opposite the U.S. Military Academy Reservation at West Point and is connected to the east shore by Constitution Marsh.

Taken briefly by the British in 1777, the island was re-occupied by American forces in 1778, and made an integral part of Fortress West Point.

Between Cold Spring and West Point lay a large rocky island connected to the eastern shore by a reedy marsh.

[1] The strategic importance of the ability to control navigation along the Hudson River was obvious to both the Americans and the British from the outbreak of open hostilities.

However, difficulties in construction and management of the original plan of fortifications, together with escalating costs, led to abandonment of that project.

[5] In 1778 Polish engineer Thaddeus Kosciusko began designing Fortress West Point as a series of forts and redoubts on both sides of the river.

The first chain, which weighed 35 tons and was 1650 yards long stretched between the base of Fort Montgomery and the rock at Anthony's Nose.

Made by Peter Townsend's Stirling Iron Works in Warwick, New York, the 1500 foot long chain weighed 186 tons.

In 1908, Mrs. Russell Sage and Miss Anna Warner presented Constitution Island to the United States government as a joint gift according to the following stipulations: “Lawrence, L.I., September 4, 1908, The President: Sir: I take pleasure in tendering as a gift to the United States from myself and Miss Anna Bartlett Warner, Constitution Island, opposite of West Point…to be an addition to the Military Academy…under the following conditions: First: That ‘the Island be for the use forever of the United States Military Academy at West Point…that no part of it shall ever be used as a public picnic, excursion, or amusement ground, operated by private enterprise, individual or corporate, for profit…” The president sent the following letter to Mrs. Sage.

The Military Academy has made improvements to the site including upgrades to the roadways, drainage, support facilities and trails.

The West Point Museum and United States Army Garrison have begun the construction of an Education Center on the island.