The Bronx is the fourth largest and the northernmost of the five boroughs, and the only one on the American mainland. Long Island Sound on the east, the Harlem and East rivers on the south, and Hudson River on the west. Largely residential, the Bronx includes dozens of vibrant neighborhoods. Fieldston is particularly elegant, with great stone houses set among spacious lawns and privately-maintained streets, while Belmont has become the city's most authentically Italian section. The areas along Pelham Parkway and the northern reaches of the Grand Concourse are particularly prized, because the apartment buildings are well kept and the public parks are easily accessible.
City Island retains the charm of a small fishing village.
Parts of the Bronx, however, fell victim to decay and abandonment, especially between 1970 and 1980, when the population of the borough fell by 20 percent. Since 1980 the process has again reversed and self-help groups have begun to rehabilitate most of the most devastated blocks. The borough's many attractions include the world-famous Bronx Zoo, Yankee Stadium, and the New York Botanical Garden. The Bronx also includes two of the largest middle-income housing projects in the United States. Parkchester, built between 1938 and 1942 for the Metropolitan Life Insurance Company, houses 40,000 people in apartment buildings arranged along well-planned circular drives.