Oxbow Preserve, Kennebunk
Though this trail was a bit overgrown when I visited in June, 2018, it is still a pleasant walk (mind the ticks, though!). From the trailhead, you walk down a fairly steep access path to the flat section of the preserve, which is nearly encircled by a Mousam River oxbow. You’ll see blazes at the bottom of the hill that will lead you on a half-mile loop.
Directions: Parking is located on Spiller Drive off of Cat Mousam Road in Kennebunk.