The Portland Metropolitan Greenspaces Program is an effort to identify, protect, and manage land and wildlife within a growing urban area. While the original intent of the program was to preserve urban natural areas, the program has expanded to include a wider variety of natural and cultural areas. Greenspaces include a 40-mile loop land trust, a metropolitan wildlife refuge system, and a regional parks inventory. The initial phase of the program included an inventory, which created maps showing the natural areas, data of the mapped areas, and a spatial database showing these areas. The program focuses on acquisition and encompasses a variety of protection strategies, and landowners may donate properties.
Funding comes from several sources, including local, state, and federal programs.
Hiking and biking corridors have been created through the 40-mile loop, and the public has indicated strong support for the program. Two of the most interesting achievements of the program have been the database and inventory, which not only define undeveloped land, but also define land in biological and ecological terms a unique way of viewing land in metropolitan areas.