Moonbow Trail

The Moonbow Trail loops along the Cumberland River gorge rim, connecting the downstream river access points with a dedicated moonbow viewing platform that was constructed to optimize the lunar rainbow observation experience unique to Cumberland Falls—a phenomenon that occurs because the falls' full-width curtain creates a sufficiently dense spray field that lunar light can excite into a full-spectrum bow on clear full moon nights from late spring through fall. The gorge rim sections of the trail provide elevated views down into the Cumberland River canyon, where the river runs green and swift through the resistant sandstone and conglomerate formations that have prevented the gorge from widening over millions of years. The mixed hardwood forest of the gorge rim—dominated by chestnut oak, scarlet oak, and Virginia pine on the dry exposed edges—gives way to richer bottomland species in the moist ravines draining toward the river, creating a botanical diversity that supports excellent fall warbler migration activity. The moonbow viewing platform at the trail's terminus sits on a sandstone promontory with an unobstructed downstream view of the falls, positioned precisely to capture the bow that forms in the mist cloud above the plunge pool when the full moon is 45 degrees above the southeastern horizon. During full moon weekends, the platform fills with photographers and observers from as far as Europe and Japan. Timber rattlesnakes are occasionally encountered sunning on the rim's sandstone outcrops in summer; they are non-aggressive and protected within the park.