| River running through the Grand Canyon |
| Coastal phenomenon |
| Canyon phenomenon |
| Pre-migraine headache phenomenon |
| Agricultural phenomenon sometimes linked to UFOs |
| Canyon critters |
| Grand Canyon area |
| Autumn lunar phenomenon |
| Alpine phenomenon |
| Phenomenon observed in receding galaxies ... and in the answers to this puzzle's asterisked clues? |
| Grand Canyon pack animals |
| First light ... or a phenomenon suggested by this puzzle's seven sets of circled letters? |
| Canal or Canyon |
| Pop culture phenomenon |
| Grand Canyon sights |
| Stock market phenomenon |
| Canyonlands National Park sights |
| Eerie phenomenon |
| Phenomenon of the Colorado River. |
| Depression phenomenon |
| Eclipse phenomenon. |
| Polar region phenomenon |
| Acoustic phenomenon |
| Canyon |
| Excavator overlooked secondary weather phenomenon |
| Unexplained phenomenon |
| Canyon comebacks |
| Orbiting phenomenon |
| Like the Grand Canyon or Fourth of July fireworks |
| Static phenomenon |