Walter Newton Natural Area Conservation Area & Waterfall This 1.5-mile loop trail near Plymouth is generally considered easy, taking an average of 33 minutes to complete. The shortest route to the base of Rainbow Falls is the Ruth Walter Trail, a well-maintained 0.6-mile trail with mostly flat and gentle terrain. The approximately 25-foot-high waterfall changes immensely with the seasons, with the best time to visit being during spring or after heavy rainfall when water levels are highest. Two benches are located at the falls to relax and take in the scenery, and a side trail brings you to the top of the falls for a different perspective. Stop at additional benches for views of the nearby wetlands, and look for moose, birds, and other wildlife.