what does the mentioned street line signify?
It is a rapid transit line of the IND Division of the New York City Subway.
IND Fulton Street Line
The IND Fulton Street Line is a rapid transit line of the IND Division of the New York City Subway, running from the Cranberry Street Tunnel under the East River through all of central Brooklyn to a terminus in Ozone Park, Queens.
where is nostrand avenue station (ind fulton street line) located? Bedford–Stuyvesant, Brooklyn, New York City
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IND Fulton Street Line [SEP] Introduction
The IND Fulton Street Line is a rapid transit line of the IND Division of the New York City Subway, running from the Cranberry Street Tunnel under the East River through all of central Brooklyn to a terminus in Ozone Park, Queens. The IND Rockaway Line branches from it just east of Rockaway Boulevard. The A train runs express during daytime hours and local at night on the underground portion of the line; it runs local on the elevated portion of the line at all times. The C train runs local on the underground portion of the line at all times except late nights.