Rural Beginnings
Through the 19th century, the area including and adjoining today's Fifth Avenue neighborhood was known as Petersville. The northwest corner of the neighborhood appeared on an 1846 "Map of a Farm Belonging to John R. Peters Situated in the Town of New Rochelle," at left. Today's Portman Road, which forms the western boundary of the study area, was labeled as "Road to the Mill"; the street was known as Mill Road at least until 1931, although the size, age, location, and purpose of the mill it refers to do not appear to have been documented. Pine Brook passed under the intersection of Portman and what is today Fifth Avenue, which, in 1846, was labeled, east of the intersection, as a private road. The land that is now City Park was labeled as the property of Alexander Ritchie, and the site of his house and barn. The intersection of what is today Portman Road and Fifth Avenue is indicated by the asterisk.

In 1855, much of the study area's western portion was in the hands of Peter Kauffman and Henry Siegel. On an 1855 map, today's Fifth Avenue was labeled as "Formerly Reebers Lane," and Pine Brook passed underneath two bridges at the intersection with "Old Mill Road." The lands east, north, and west of Kauffman's and Siegel's holdings were labeled as "Village of Petersville." Today's Fifth Avenue west of the study area was called Peters Road. The asterisk at right indicates the same location as on the 1846 map.

In 1856, today's City Park property was still owned by Alexander Ritchie. The lands east of Ritchie's property and between the study area and the main line of the New York and New Haven Railroad had been subdivided. The railroad, which was completed through New Rochelle in 1848, is seen as a heavy black line running across the bottom of the map. According to the map's title, the subdivided properties belonged to an organization called the Petersville Homestead Association. Siegel and Kauffman retained the lands in the western portion of the study area. The MacLeay Apartments now stand on the site of the subdivided properties at the upper-right portion of the map. The eastern two-thirds of the study area was labeled "Land of Lorenz Bielm," possibly corrupted into "Biehn," the name of a street currently located within the study area. The jagged southern boundary of Bielm's holdings today forms the southern boundary of the study area. Fifth Avenue was called Morris Avenue; the asterisk indicates what is today the intersection of Fifth Avenue and Portman.

Little development took place in the study area before the early 20th century. The 1901 Bromley map of the neighborhood, shown at right, indicates that no building had taken place in the subdivided areas north and south of the study area. Siegel's and Kauffman's properties had been acquired by James Burns and Fred Krause, who had erected a few wooden buildings and auxiliary structures on their property. Pine Brook continued to run underneath the jagged intersection of what is today Fifth Avenue, but was then known as Morris Avenue east of Mill Road and Peters Road west of Mill. The Petersville name remained north of the study area. The asterisk indicates the same location as on the 1846, 1855, and 1856 maps.

Urbanization
By 1907 Bielm's, Burns's, and Krause's former properties were owned by Frederick Lorenzen. A map filed that year with the Westchester County Registrar called the district "Fifth Avenue Park," possibly in anticipation of the construction of City Park across Fifth Avenue from the neighborhood. The study area was neatly subdivided into lots as close in size to 25-by-100 feet as was possible within the irregular boundaries of the site. This lot size, the standard for developers of New York City rowhouses during the 19th century, indicates that Lorenzen envisioned the neighborhood as a dense, urban district. Despite the new name, the map described the area as "part of map of the Village of Petersville." Fifth Avenue had acquired its present name, and Pine Brook had been redirected, apparently into a pipe, which ran underneath the neighborhood and the intersection of Mill and Fifth.

The neighborhood underwent substantial changes around 1910. That year, the City of New Rochelle purchased the land that was to become City Park. According to local historian Herbert B. Nichols, writing in 1938, "The park contains nearly 30 acres, a part of which has been left as natural woodland. The rest, with a suitable athletic building, has been conditioned into baseball diamonds, football fields, and a running track." The Municipal Recreation Building described by Nichols was completed in 1923 and designed by Lawrence M. Loeb, an architect of several Westchester County residences. The building, visible at left, still stands, although boarded up and unused, in City Park.

Just as significantly, 1910 was the year in which the trolley was extended to the study area. By that time, New Rochelle had developed a sophisticated trolley system that had begun in 1885 with the organization of the New Rochelle and Pelham Railway Company and the New Rochelle Street Horse Railway Company. From City Park, riders could travel down Fifth Avenue to North Avenue, where they could transfer to the trolley that would take them downtown. A Main Street line from Downtown traveled to Mamaroneck; a connection to Mount Vernon made it possible to ride all the way to New York City. So popular were the trolleys and so willing were their patrons to travel long distances that, according to Nichols, "The trolley and its connection with New York City had been fought by local merchants because they feared that shoppers would take the trolley to New York instead of shopping in New Rochelle." By the 1940s, as throughout the country, buses had replaced many trolley lines.

By 1910, home builders had already begun subverting Lorenzen's orderly, dense subdivision plan. The 1910 Bromley map, at right, shows 11 wooden buildings and one wooden auxiliary structure present in the study area, all on combined lots; 146 Pleasant, for example, is tucked into the corner of what was originally conceived of as three lots, and three houses on Plain Avenue share a frontage of 125 feet, or five lots.

The 1915 New York State Census provided a thumbnail sketch of the neighborhood's population. All of the neighborhood's houses were single-family dwellings, and the male heads of household were primarily laborers or other blue-collar workers. Fifth Avenue's residents included natives of Germany, Italy, Russia, and Poland. Plain Avenue's residents were from Italy, Scotland, Ireland, Germany, Sweden, and England. Pleasant Street was entirely Italian, except for a German bookbinder, his Irish wife, and their two American-born daughters.

Subdivision of area properties continued into the 1920s. In 1925, Rosina B. Krause subdivided her land along the east side of Mill Road near Sharot Street into 18 properties, 16 of which had 25-foot frontages. Again, however, dense development did not follow; by 1929, five of the lots were purchased by the Sheffield Farms Dairy, which erected the milk distribution center shown at left. The structure, now occupied by the New Rochelle Humane Society, included, according to the 1931 Sanborn Fire Insurance Map, an office, wagon storage, and feed storage.

In 1928, the study area was not zoned as a purely residential district. Those areas that were residential were zoned for multiple dwellings. The entire block bounded by Fifth Avenue, Mill Road, Plain Avenue, and Valley Place was zoned "O," or "business." The south side of Plain was also zoned for businesses. Both sides of Pleasant Street were zoned "C" or "multifamily residential." The "O" zoning accommodated modifications and uses such as those present at 71 Plain, where a store was added on to the front of a 1914 Dutch Colonial Revival house typical of many built throughout the neighborhood during its early years.

By 1929, the neighborhood had considerably filled in. The 1929 Hopkins Atlas showed several masonry buildings to have been constructed, particularly along both sides of Pleasant Street and the south side of Plain Avenue between Biehn and Valley. The Fifth Avenue trolley line terminated at Fifth Avenue and Mill Road. The property between the study area and the railroad tracks was labeled "Pelham-Port Chester Parkway," indicating the proposed route of a highway running from Fairfield County, Connecticut to the Bronx along the eastern portion of Westchester County. The lands between Mill Road and the Mamaroneck town line near the eastern portion of the study area, which were never built upon, were acquired by Westchester County in the early 1930s. Although the parkway was never built, this property was used as the right-of-way for the New England Thruway (the Westchester County portion of Interstate 95), which opened, in its entirety, on October 15, 1958. East of City Park, where the MacLeay Apartments were constructed in 1949, were approximately eight buildings, all, except for one, built out of wood.

On the 1931 Sanborn Map, the study area is shown to be primarily residential, with some important exceptions. Fifth Avenue, similar to today, had mixed commercial and residential uses, with dwellings interspersed with stores, two contractors' yards, storage areas, a sheet-metal works, and a gas station in the same location as today's Citgo station. The north side of Plain Avenue was entirely residential, except for a factory located near Mill Road; the south side was also entirely residential, except for the store, previously mentioned, at 71 Plain. Pleasant Street was entirely residential. Even so, the neighborhood must have had a similar jumbled appearance to today's; most dwellings had auxiliary buildings, likely chicken coops or storage sheds. Moreover, the large number of open lots in the neighborhood, still present, prevented the creation of a continuous residential streetscape, except for the small residential enclaves on the south side of Pleasant Street and the north side of Plain.

Significant change came to the neighborhood in 1955, when it was zoned as an M-1 Light Manufacturing District. Since then, residential and industrial uses have shared the study area. No new houses have been built in the neighborhood since the rezoning, which prohibits residences, and several former houses, such as 53 Pleasant Street, have been converted to commercial use.

Buses, which took over New Rochelle's trolley routes beginning in the 1940s, proved to be a mixed blessing. Although the new, air-conditioned buses initially elicited "applause from merchants and shoppers who crowded the curbs" to see them in Downtown New Rochelle, inconsistent service ultimately followed, likely decreasing the Fifth Avenue neighborhood's appeal. The Fifth Avenue bus line was extended to Valley Place by 1973, where it looped back along Plain Avenue, but this may have decreased the attractiveness of the neighborhood. When bus service had been extended through a primarily African-American neighborhood in 1967, for example, one resident called it a "Stab in the back to Negroes," protesting to his Councilman, "Is it because Negroes now own the properties along this route on Lincoln Avenue and the surrounding area why you decided to give them more air pollution with the accompanying noise and litter?"

New Rochelle's bus operators ultimately hit hard times; but 1970, the intervention of the County Executive was needed to prevent termination of Sunday service on some city lines, and in 1974, service cutbacks of 15% were imposed in some areas due to financial hardship. Today, the No. 61 route of the Westchester County Bee-Line bus, operated by Liberty Lines, stops at City Park approximately every half hour on weekdays on its way to Downtown New Rochelle.