Bungalows and vacation houses were built on the coast of "Flatlands Bay", around Bergen Island, before World War I. However, city records from 1909 to 1915 do not indicate where exactly these houses were erected. In 1927, the New York City Department of Docks began leasing lots and bungalows on Bergen Beach. As of 1930, the yearly rates for these lots ranged between $10 and $240 (worth between $ and $ in ). Bergen's house itself was demolished during the construction of Belt Parkway, also known as the Shore Parkway, in the 1930s. When the parkway opened in 1936, though, it did not spur development in Bergen Beach. The 1939 WPA Guide to New York City mentions that the area comprising present-day Mill Basin and Bergen Beach was the residence of "pathetic communities of squatters, who live in makeshift houses, and eke out a living by fishing and scouring the near-by city dumps for odd necessities". At the time, the southern shore was still marshland. Although fourteen single-family houses were built in the 1940s, much of the neighborhood retained a rural character through the 1960s.