40-Mile Loop

The 40-Mile Loop is a partially completed greenway trail around and through Portland in the U.S. state of Oregon. It was proposed in 1903 by the Olmsted Brothers architecture firm as part of the development of Forest Park. One greenway expert calls it "one of the most creative and resourceful greenway projects in the country."

The name's "forty" was obsolete within a few decades after it was proposed. The proposed total path is now about 140 miles (230 km) long, and connects more than thirty city parks. Similarly, "loop" is not entirely accurate. There are several subloops, cutoffs and spur trails within the system. One spur is proposed to connect to the Pacific Crest Trail.