Appalachian Corridor’s territory of action is a critical linkage within the Northern Appalachian/Acadian ecoregion. This ecoregion is unique, and uniquely challenged: we know of nowhere else in the world where so much forest is located so close to so many people. It spans two countries, five US states and four Canadian provinces; it contains species at risk, old-growth forests and 5.4 million people.

Preliminary studies reveal that this ecoregion risks being separated into a series of ecological islands. Protection of key landscape linkages, including the Northern Green Mountains, is a critical need. Appalachian Corridor, along with 50 conservation organisations, researchers, and foundations is involved with  Two Countries, One Forest (2C1Forest), an international organisation dedicated to using landscape conservation to protect and maintain the Northern Appalachian/Acadian ecoregion.