Atlantic Avenue is a major thoroughfare in the New York City boroughs of Brooklyn and Queens. It stretches from the Brooklyn waterfront on the East River all the way to Jamaica, Queens. Atlantic Avenue runs parallel to Fulton Street for much of its course through Brooklyn, where it serves as a border between the neighborhoods of Prospect Heights and Fort Greene and between Bedford-Stuyvesant and Crown Heights, and between Brooklyn Heights and Cobble Hill. This stretch of avenue is known for having a high rate of pedestrian fatalities and has been described as "the killing fields of the city."

Brooklyn is a borough of New York City. Located on the westernmost end of Long Island, it is coextensive with Kings County in the U.S. state of New York. With 2,736,074 residents as of the 2020 United States census, Kings County is the most populous of the five boroughs of New York City and the most populous county in the State of New York. The population density of Brooklyn was 37,339.9 inhabitants per square mile (14,417.0/km2) in 2022, making it the second-most-densely-populated county in the United States, behind Manhattan, and it had the ninth-highest population of any county nationwide. Were Brooklyn still an independent city, it would be the fourth most populous in the U.S. after the rest of New York City, Los Angeles, and Chicago.