The Boston Harbor Islands became a unit of the National Park System in November 1996 by an act of Congress (16 USC 460kkk) that contains several provisions which, in total, make this a national park like no other. It includes 34 islands that lie within the large "C" shape of Boston Harbor. Managed by a unique Partnership, the islands have been closely linked to Massachusetts Bay and to coastal communities for thousands of years. The land mass of the Boston Harbor Islands totals approximately 1,600 acres at high tide and 3,100 acres at low tide. The Boston Harbor Islands national park area extends seaward 11 miles from downtown Boston. The Boston Harbor Islands form a transition between the open ocean and the settled coast, between the world beyond Boston Harbor and the features specific to it. They are not only a physical entrance but a gateway as well to a long sweep of history, from Native American uses through the explosive growth of the city and industry and the concerns of the current post industrial age. The only drumlin field in the United States that intersects a coast, 35 miles of relatively undeveloped shoreline within a densely settled urban area, resources associated with thousands of years of occupation by American Indians, and the complex natural communities of the intertidal zones all illustrate the intrinsic value of Boston Harbor Islands resources.
Both literally and symbolically, the islands offer a unique vantage point from which visitors can contemplate metropolitan growth and change. The islands also offer an exceptional perspective on change in the region's ecosystem. Magnificent open spaces surrounded by expanses of open water, the islands vividly illustrate the region's complex geological past and the continual effect of natural processes on their habitats, their uses, even their shapes. From them, visitors can learn about how such complex ecosystems as harbors are revived. The improvement of Boston Harbor waters has regenerated the biotic communities of the islands and the sea around them and has made possible an impressively wide range of recreational uses. Thus the islands are both a recreational haven for urban residents and tourists and a highly effective laboratory in which to learn about natural change, cultural history, and stewardship.
While the legal name is Boston Harbor Islands National Recreation Area, the park is known as Boston Harbor Islands, a national park area. This latter name was chosen by the Boston Harbor Islands Partnership at the behest of American Indians and in consultation with the National Park Service Washington office. The Indian nations that were involved in King Philip's War strongly voiced their opposition to the word "recreation" and believed it was inappropriate and disrespectful to their ancestors who were incarcerated, died, and were buried on the islands (see "Native Americans and the Islands"). This change allows the park to foster public understanding and appreciation for Indians' strongly felt view of the islands as sacred ground. It focuses more on the park's resources and history than on recreation.
Until 1970, when the Commonwealth of Massachusetts began systematically to acquire them for the benefit of the public, the islands of Boston Harbor had been shielded from public view and appreciation for generations by commercial and industrial development along the waterfront and by the poor quality of harbor water. In 1985, Boston Harbor was labeled the most polluted harbor in the nation, but the dramatic recovery of water quality during the 1990s, through the Massachusetts Water Resources Authority's wastewater treatment, contributed to widespread support for establishing a national park area. Now, after an investment of more than $4 billion in better wastewater management and treatment, the harbor is cleaner and more inviting. Over the past three decades, numerous public and private agencies have once again turned their focus to Boston Harbor and its islands, as the region seeks to rebuild its historical and ecological ties to Massachusetts Bay.
The 34 islands of Boston Harbor (ranging in size from less than 1 acre to 274 acres) have served numerous public and private uses and are a unique example of an island cluster intimately tied to the life of a city. Although within sight of a dynamic and densely populated metropolitan area, they continue to offer the visitor a rare sense of isolation. Their proximity to a large urban population and their special natural and geologic resources, cultural and historic resources, and associated values contribute to their national significance.