100% | NIAGARA | 7 | River that forms part of the U.S.-Canada border |
75% | GUADIANA | 8 | River that forms part of the Spain-Portugal border |
75% | RHINE | 5 | River that forms part of the France/Germany border |
75% | WABASH | 6 | River that forms part of the Illinois-Indiana border |
74% | ODER | 4 | River that forms part of the border between Germany and Poland |
74% | ORINOCO | 7 | River that forms part of the border between Colombia and Venezuela |
74% | MOSELLE | 7 | River that forms part of the border between Germany and Luxembourg |
74% | DOURO | 5 | River that forms part of the border between Spain and Portugal |
74% | RIONEGRO | 8 | River that forms part of the border between Colombia and Venezuela |
73% | ELBE | 4 | River that formed part of the border between East and West Germany |
71% | DOURO | 5 | River that forms part of the border between Spain and Portugal before flowing west to the Atlantic |
66% | DEE | 3 | River that forms part of the England/Wales boundary |
65% | ERIE | 4 | Part of the U.S./Canada border |
65% | YALU | 4 | River that forms a large part of the border between North Korea and China |
64% | MAMORE | 6 | River rising in the Andes that forms part of the Bolivia-Brazil border |
62% | KASAI | 5 | Tributary of the Congo River that forms part of the border between the Democratic Republic of the Congo and Angola |
61% | SNAKE | 5 | — River, US watercourse forming part of the border between Idaho and Oregon |
61% | RED | 3 | Texas' ___ River, formerly part of the U.S./Mexico border |
61% | MEKONG | 6 | River that forms much of the Laos/Thailand border |
60% | TAMAR | 5 | River that forms most of the border between Cornwall and Devon |
58% | ARAS | 4 | River forming part of the border between Azerbaijan and Iran |
58% | MOSELLE | 7 | River forming part of the border between Germany and Luxembourg |
56% | EAST | 4 | Part of the U.S. that's usually first with election returns |
55% | DEADSEA | 7 | Salty lake that forms part of Jordan's border |
55% | OHIO | 4 | River that forms much of Kentucky's border |
54% | BERMEJO | 7 | River of N Argentina forming part of the border with Bolivia |
54% | PERU | 4 | The Putumayo River forms part of its northern border |
54% | ULNA | 4 | Bone that forms part of the forearm |
54% | IOWA | 4 | The Mississippi and Missouri rivers form parts of its border |
53% | IOWA | 4 | The Big Sioux River forms part of its border |