sentences:  A significant portion of the neighborhood lies within the Upper East Side Historic District designated by the New York City Landmarks Preservation Commission in 1981 and expanded in 2010.The neighborhood is part of Manhattan Community Board 8.Based on the location of the original Lenox Hill, which was on a farm that spanned present-day 68th Street to 74th Street, east of Fifth Avenue, "The Encyclopedia of New York City" defines the neighborhood as the area between 60th Street and 77th Street, from Fifth Avenue on the west to Lexington Avenue on the east.