Context: The character of New York's large residential districts is often defined by the elegant brownstone rowhouses and townhouses and shabby tenements that were built during a period of rapid expansion from 1870 to 1930. In contrast, New York City also has neighborhoods that are less densely populated and feature free-standing dwellings. In neighborhoods such as Riverdale (in the Bronx), Ditmas Park (in Brooklyn), and Douglaston (in Queens), large single-family homes are common in various architectural styles such as Tudor Revival and Victorian.

Question: In what borough is the Riverdale neighborhood located?
Answer: the Bronx

Question: In what borough is the Ditmas Park neighborhood located?
Answer: Brooklyn

Question: In what borough is the Douglaston neighborhood located?
Answer: Queens

Question: Brownstone rowhouse construction is most often associated with the period beginning in 1870 and ending in what year?
Answer: 1930

Question: Along with Tudor Revival, what is a common architectural style of single-family houses in New York?
Answer: Victorian

Question: What type of housing structure makes up most of the large residential districts of NYC?
Answer: brownstone rowhouses