| 100% | CANYON | 6 | Grand ___, natural wonder carved by the Colorado River about 5 to 6 million years ago |
| 33% | GRANDCANYON | 11 | Gorge carved by the Colorado River |
| 26% | SONORA | 6 | State bordered by the Colorado River |
| 26% | ERODE | 5 | What the Colorado River will continue to do to the canyon for a few more zillion years |
| 25% | SQFT | 4 | About 6.5 million for the Pentagon: Abbr. |
| 25% | INCA | 4 | Civilization in the Andes Mountains about 500 to 800 years ago |
| 25% | GRAND | 5 | Deep gorge formed by the Colorado River in northern Arizona, US |
| 24% | ICON | 4 | Item you learned to paint about 300 years ago at the Aleppo School, founded by Yusuf al-Musawwiror "Joseph the Painter" |
| 24% | GRAND | 5 | & 17A Deep gorge formed by the Colorado River in northern Arizona, US |
| 23% | EOCENE | 6 | Occurring 40 to 55 million years ago |
| 23% | GILA | 4 | River to the Colorado |
| 23% | VOLGA | 5 | River connected by canal to the Don |
| 23% | ARNO | 4 | River connected by canal to the Tiber |
| 23% | NEVA | 4 | River connected by canal to the Volga |
| 22% | PLIOCENE | 8 | Epoch from 10 to 2 million years ago |
| 22% | PLIOCENE | 8 | Epoch from two to five million years ago |
| 22% | ERA | 3 | Mesozoic ___ (252 to 66 million years ago) |
| 22% | MOHAVE | 6 | People indigenous to the Colorado River |
| 22% | LASTSONG | 8 | Novel by Nicholas Sparks about a 17 year old teen who is sent to stay with her father in the summer, "The ___": 2 wds. |
| 22% | AMAZONRAINFOREST | 16 | Natural wonder that's roughly 1,100 times bigger than the Grand Canyon? |
| 22% | ERODED | 6 | What the Appalachian Mountains have done since about 480 million years ago |
| 21% | AGO | 3 | "More than 200 million years ___, 15a began to evolve and roam the Earth..." |
| 21% | STONEAGE | 8 | It started about 2 1/2 million years ago |
| 21% | RIOGRANDE | 9 | River that flows from Colorado to the Gulf of Mexico: 2 wds. |
| 21% | ODYSSEY | 7 | "The ___," ancient Greek poem by Homer about a warrior lost at sea for years, trying to find his way home |
| 21% | URBANAREA | 9 | Home to about 4 in 5 Americans, per the census |
| 21% | ENDURE | 6 | Last to finish by the river |
| 21% | PEARL | 5 | "Mama's ___," 1970 song by the Jackson 5 that is about a mama's girl |
| 21% | GED | 3 | Substitute acquired by about half a million people a year: Abbr. |