Fort Jay is a historical United States Army fort on Governors Island in New York City. The oldest structure on the island, it was originally built to defend Upper New York Bay, but has served other purposes. The Army is the branch of the United States armed forces which has primary responsibility for land-based military operations. ... Fortifications (Latin fortis, strong, and facere, to make) are military constructions designed for defensive warfare. ... Governors Island, shown in red, in Upper New York Bay Governors Island is a 172 acre (696,000 m²) island in Upper New York Bay, approximately one half mile from the southern tip of Manhattan, of which it is legally a part, in New York City. ... Midtown Manhattan, looking north from the Empire State Building, 2005 New York City (officially named the City of New York) is the most populous city in the United States, and is at the center of international finance, politics, communications, music, fashion, and culture. ... Upper New York Bay, sometimes called Upper New York Harbor or the Upper Bay, is the northern area of New York Harbor inside the Narrows. ...

The walls and gate of the existing fort were rebuilt in 1806 to replace a series of earthen forts built in 1776 and 1794. Barracks on the inside of the fort date back to 1834, first as officers housing, then family housing from the 1930s to 1996. The cannons that are still in place date to the American Civil War period, around 1861, and had an accurate range of one mile. 1806 was a common year starting on Wednesday (see link for calendar). ... This article is about the year 1776. ... 1794 was a common year starting on Wednesday (see link for calendar). ... 1834 was a common year starting on Wednesday (see link for calendar). ... The American Civil War was fought in the United States from 1861 until 1865 between the United States – forces coming mostly from the 23 northern states of the Union – and the newly-formed Confederate States of America, which consisted of 11 southern states that had declared their secession. ... 1861 is a common year starting on Tuesday. ...

The square shaped fort is surrounded by a five-pointed star shaped dry moat. The moat is in turn surround by a sloped grassy area, cleared of trees, that would provide no cover for any advancing enemy forces. In the twentieth century, this grass surrounding the fort was used as a golf course by the army until 1996. 1996 is a leap year starting on Monday of the Gregorian calendar, and was designated the International Year for the Eradication of Poverty. ...

The entrance gate is crowned by a sandstone carving of the United States Department of War insignia. The United States Department of War was the military department of the United States governments executive branch from 1789 until 1949, when it became part of the United States Department of Defense. ...

Fort Jay was originally named for named for John Jay, but was renamed Fort Columbus at the completion of its reconstruction in 1808. The original name, Fort Jay, was restored in 1904. John Jay, first Chief Justice of the United States Oil painting by Gilbert Stuart, 1794 John Jay (December 12, 1745 – May 17, 1829) was an American politician, statesman, revolutionary, diplomat and jurist. ... 1808 was a leap year starting on Friday (see link for calendar). ...