Blue Line (New York State)

The Blue Line is the term used in New York state for the boundaries of the Adirondack and Catskill parks, within which can be found the state's Forest Preserve. The state constitution requires that any property owned or acquired by the state in those parks "be forever kept as wild forest lands" and prohibits it from selling or transferring them in any way (save amending that section of the constitution to allow specific transactions).

It is so called because blue ink was used when they were first drawn on state maps. That started a tradition that persists to this day (although private mapmakers have just as often used green). While they were originally meant merely to guide the acquisition of future Forest Preserve land, over time they have come to define and have legal impact on all lands, public and private, within them.

When the Forest Preserve was created in 1885, the legislature merely designated particular counties in the state as places where Forest Preserve could be acquired in the future. This definition was retained nine years later when the Forest Preserve Act became Article 14 of the state constitution.

Shortly afterwards, it became apparent that a more precise definition was needed, as some of the counties in which there was the greatest need to protect land also had large areas where that was not necessary. Ulster County, for instance, is home to some of the wildest land in the Catskills but also has many well-developed lowlands near the Hudson River.

So, in 1902, the legislature passed a bill defining the Adirondack Park for the first time in terms of the counties and towns within it.

Two years later, the Catskill Park followed suit. However, it was delineated not solely in terms of pre-existing political boundaries but instead through a combination of those and old survey lot lines, streams and railroad rights-of-way. That proved to be a more effective and politically viable method, and accordingly the Adirondack Park Blue Line was redrawn shortly afterwards following the Catskills' example.

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