[13] To the south lay Kip's Bay farm; to the north, on a bluff, stood James Beekman's "Mount Pleasant", the first of a series of houses and villas with water views stretching away up the shoreline.

After the street grid system was initiated in Manhattan, the hilly landscape of the Turtle Bay Farm was graded to create cross-streets and the land was subdivided for residential development.

An army enrollment office was established at Third Avenue and 46th Street, after the first Draft Act was passed during the American Civil War.

On July 13, 1863, an angry mob burned the office to the ground and proceeded to riot through the surrounding neighborhood, destroying entire blocks.

The New York Draft Riots continued for three days before army troops managed to contain the mob, which had burned and looted much of the city.

The cove was filled in after the Civil War, serving as a valuable shelter from the often harsh weather on the river, and became a thriving site for shipbuilding.

By 1868 the bay had been entirely filled in by commercial overdevelopment, packed with breweries, gasworks, slaughterhouses, cattle pens, coal yards, and railroad piers.

[14] By the early 20th century, Turtle Bay was "a riverside back yard" for the city, as the WPA Guide to New York City (1939) described it: "huge industrial enterprises—breweries, laundries, abattoirs, power plants—along the water front face squalid tenements not far away from new apartment dwellings attracted to the section by its river view and its central position.

With an infusion of poor immigrants having had come in the later part of the 19th century, and the opening of the elevated train lines along Second and Third Avenues, the neighborhood went into decay with crumbling tenement buildings.

In 1918 she purchased twenty houses on 48th and 49th Streets between Second and Third Avenues; within two years she had renovated the enclave called Turtle Bay Gardens.

[21] The clearing of the slaughterhouses for the construction of the UN headquarters in 1948, largely completed by 1952, and the removal of the elevated trains opened the neighborhood up for high-rise office buildings and condominiums.

[22] Until the Third Avenue El was demolished in 1956, it was characterized by a blighted stretch of sooty darkness that had separated the neighborhood from Midtown Manhattan.

In October 2011, city and state officials announced an agreement in which the UN would be allowed to build the tower adjacent to the existing campus on the current playground.

[26] Based on data from the 2010 United States Census, the population of Turtle Bay-East Midtown was 51,231, a change of 1,494 (2.9%) from the 49,737 counted in 2000.

Based on this calculation, as of 2018[update], Turtle Bay and Stuyvesant Town are considered to be high-income relative to the rest of the city and not gentrifying.

[28]: 7 To the north of Turtle Bay is Sutton Place, to the west is Midtown, and to the south are Tudor City and Murray Hill.

[32] The Turtle Bay Association, a neighborhood non-profit 501(c)3 organization, was founded in 1957[33] by James Amster[34] to protest, successfully, the widening of East 49th Street.

The Association's efforts have resulted in more park and landscaping development, creating the neighborhood's tree-lined and relatively quiet atmosphere.

In the southern section of Turtle Bay, between 42nd and 43rd Streets east of Second Avenue, the Ford Foundation Building and its lobby interior are designated as city landmarks.

[28]: 14 The concentration of fine particulate matter, the deadliest type of air pollutant, in Turtle Bay and Stuyvesant Town is 0.0102 milligrams per cubic metre (1.02×10−8 oz/cu ft), more than the city average.

[28]: 13  In Turtle Bay and Stuyvesant Town, 10% of residents are obese, 5% are diabetic, and 18% have high blood pressure—compared to the citywide averages of 24%, 11%, and 28% respectively.

[28]: 6  The percentage of Turtle Bay and Stuyvesant Town students excelling in math rose from 61% in 2000 to 80% in 2011, and reading achievement increased from 66% to 68% during the same time period.

[79] Turtle Bay and Stuyvesant Town's rate of elementary school student absenteeism is lower than the rest of New York City.

[29]: 24 (PDF p. 55) [28]: 6  Additionally, 91% of high school students in Turtle Bay and Stuyvesant Town graduate on time, more than the citywide average of 75%.