Septuagesimo Uno

While it's not smallest piece of park property in New York, Septuagesimo Uno is still a charmingly diminutive plot of land, occupying a mere 0.04 acres between two townhouses on West 71st Street. 

The creation of the park may date to Mayor John Lindsay's era, but its roots lie in the Commissioners Plan of 1811, which laid out the Manhattan grid system of roads with 12 avenues and 155 cross-streets. Parks were included in the plan at 53rd, 66th, 77th and 120th Streets. But, while the plan was effective at predicting and handling the explosive growth the city would experience over the next 150 years, it ultimately failed to provide enough parkland for recreation. 

To help alleviate demand, Mayor Lindsay started up the Vest Pocket Park campaign, which squeezed public space in wherever it could. The lot on 71st Street was condemned in 1969, landscaped by the city and eventually handed over to the stewardship of the NYC Parks Department in 1981. 

As for its name? It's Latin for "seventy-one," and was appended by parks commissioner Henry J. Stern in 2000 after a $14,325 renovation. Its original name was the much blander "71st Street Plot."