Several different tribes occupied the area, including The Manhattans, and the Weckquaesgeek and Siwanoy bands of the Wappinger in the south, and Tankiteke, Sintsink and Kitchawank Wappinger in the north.The first European explorers to visit the Westchester area were Giovanni da Verrazzano in 1524 and Henry Hudson in 1609.Municipal and County owned parks provide access to beaches, nature preserves and passive and active waterfront recreational facilities.Several large harbors lie along the shore including Milton Harbor in Rye, Mamaroneck Harbor, Larchmont Harbor, and Echo Bay, and the upper and lower harbors in southern New Rochelle. Army's Fort Slocum, is currently unoccupied but is slated for use as passive parkland; Glen Island, currently a Westchester Parks Department run beach and park, was one of the first amusement parks in the country serving as a summer resort at the turn of the twentieth century; Huckleberry Island is largely undeveloped, and has one of the largest rookeries in western Long Island Sound; Echo Island is owned and used by a private yacht club; Execution Rocks is the site of a 19th-century lighthouse listed on the National Register of Historic Places; Columbia, Pea, and Goose Islands are undeveloped; Clifford, Harrison and Tank Islands are part of the "Five Islands Park" and nature preserve; while Oak and Pine Islands are used as private residences.Westchester was the first suburban area of its scale in the world to develop, due mostly to the upper-middle-class development of entire communities in the late 19th century and the subsequent rapid population growth.Because of Westchester's numerous road and mass transit connections to New York City, as well as its shared border with the Bronx, the 20th and 21st centuries have seen much of the county, particularly the southern portion, become nearly as densely developed as New York City itself.A number of islands can be found off the Long Island Sound shore, most of which are located in New Rochelle. The widest section of the Hudson River, at 3.6 miles (6 km), is found between the Westchester and Rockland County shorelines immediately north of Croton Point.In Colonial times, this area was called the Tappan Zee or Sea.
It is bordered on the west side by the Hudson River and on the east side by the Long Island Sound and Fairfield County, Connecticut. Westchester's Long Island Sound shore is generally rocky, interspersed with tidal mud flats, marshes and wetlands, as well as several natural and artificially-maintained sand beaches.
The development of Westchester's parks and parkway systems supported existing communities and encouraged the establishment of new ones, transforming the development pattern for Westchester.