It is bounded by Sunset Park to the north, Dyker Heights to the east, the Narrows and the Belt Parkway to the west, and Fort Hamilton Army Base and the Verrazzano-Narrows Bridge to the south.

The section of Bay Ridge south of 86th Street is sometimes considered part of a sub-neighborhood called Fort Hamilton.

Bay Ridge was formerly the westernmost portion of the town of New Utrecht, comprising two smaller villages: Yellow Hook to the north and Fort Hamilton to the south.

The arrival of the New York City Subway's Fourth Avenue Line (present-day R train) in 1916 led to its development as a residential neighborhood.

[6] South Brooklyn was originally settled by the Canarsee Indians, one of several indigenous Lenape peoples who farmed and hunted on the land.

The Canarsee Indians had several routes that crossed Brooklyn, including a path from Fulton Ferry along the East River that extended southward to Gowanus Creek, Sunset Park, and Bay Ridge.

[7]: 9 The first European settlement at Bay Ridge occurred in 1636 when Willem Adriaenszen Bennett and Jacques Bentyn purchased 936 acres (379 ha) between 28th and 60th Streets, in what is now Sunset Park.

[9][10][a] However, after the land was purchased in the 1640s by Dutch settlers who laid out their farms along the waterfront, the Canarsee were soon displaced, and had left Brooklyn by the 18th century.

The mostly-immigrant laborers in the area started to create a community to the fort's north and west, which included stores, houses, churches, and a school.

[21]: 2 [22] In the mid-19th century, a large number of country houses were built in Bay Ridge, especially along Shore Road, which faced the New York Harbor to the west.

[25][b] Until the late 19th century, Bay Ridge would remain a relatively isolated rural area,[21]: 4  reached primarily by stagecoaches, then by steam trolleys after 1878.

[46] By the 1910s, there were two proposals to build a tunnel splitting from the Fourth Avenue subway in Bay Ridge, either at Fort Hamilton or at between 65th and 67th Streets.

[55] By the time the bridge was approved by the city's Board of Estimate in 1943, residents of Bay Ridge had turned against it, citing a detrimental impact to the neighborhood's character.

[68] Eleven houses had to be vacated after they suffered significant damage, and many of the trees on the two blocks toppled, landing on cars and stoops.

[75] In 2018, an estimated 19% of Bay Ridge and Dyker Heights residents lived in poverty, compared to 21% in all of Brooklyn and 20% in all of New York City.

Based on this calculation, as of 2018[update], Bay Ridge and Dyker Heights are considered to be high-income neighborhoods relative to the rest of the city.

Later in the 20th century, like other areas in southern and southwestern Brooklyn, there was an increase in the number of Irish, Italian, Greek, Russian, Polish, Jordanians, Lebanese, Syrian, Egyptian and to a lesser extent Chinese, people living in Bay Ridge.

In the 1990s and 2000s, many decades-old two-family houses were demolished and replaced by condominiums known colloquially as "Fedder Homes", after the branded air conditioners poking out from the buildings' facades.

Historic Fort Hamilton Army Base is located in the southwestern corner of the New York City borough of Brooklyn, with gates in Bay Ridge and Dyker Heights, and is one of several posts that are part of the region which is headquartered by the Military District of Washington.

[72]: 11  Bay Ridge and Dyker Heights has a high population of residents who are uninsured, or who receive healthcare through Medicaid.

[72]: 14 The concentration of fine particulate matter, the deadliest type of air pollutant, in Bay Ridge and Dyker Heights is 0.0074 milligrams per cubic metre (7.4×10−9 oz/cu ft), lower than the citywide and boroughwide averages.

[72]: 13  In Bay Ridge and Dyker Heights, 28% of residents are obese, 15% are diabetic, and 31% have high blood pressure—compared to the citywide averages of 24%, 11%, and 28% respectively.

[121] Mike Long, who served as chairman of the Conservative Party of New York from 1988 to 2019, owned a liquor store and resided in the district.

An exception was Democrat Sal Albanese, who was elected to the neighborhood's City Council seat in 1983, defeating the 21-year incumbent Republican-Conservative Minority Leader Angelo G. Arculeo, and went on to represent the district for 15 years.

[129] Bay Ridge and Dyker Heights have a ratio of college-educated residents similar to the rest of the city's as of 2018[update].

[130] Bay Ridge and Dyker Heights' rate of elementary school student absenteeism is lower than the rest of New York City's.

In 2004 it received a $2.1 million renovation, including new furniture and shelving, new lighting equipment, a new roof, and 27 additional public access computers.

[143] Additionally, there are MTA express bus routes X27, X37 which mainly serve for the commute to Manhattan, but also run during off-peak hours on weekdays.

Many Bay Ridge commuters opt for the relative comfort and convenience of the express bus, even though it costs more than the subway.

[144] The freight-only Bay Ridge Branch connects car floats to the Long Island Rail Road.