the residential core of manhattan, once concentrated in lower manhattan, moved uptown during the late 19th century. many stores established in the 1850s and 1860s were located along broadway south of 14th street, including the grand street flagship store of lord & taylor. by the 1870s, stores were being established between 14th and 23rd streets in the ladies' mile area. at the beginning of the 20th century, development was centered on fifth avenue north of 34th street, where new department store buildings were quickly replacing the street's brownstones. the first of these was the b. altman and company building, which opened in 1906.