| Border | Answer | % Correct | |
|---|---|---|---|
| E | Peru | Ecuador | 94%
|
| W | England | Wales | 94%
|
| G | Armenia | Georgia | 93%
|
| Z | Namibia | Zambia | 93%
|
| J | Palestine | Jordan | 92%
|
| L | Syria | Lebanon | 92%
|
| N | Ireland | Northern Ireland | 91%
|
| P | Argentina | Paraguay | 91%
|
| Q | Ontario | Québec | 91%
|
| R | Moldova | Romania | 91%
|
| D | Maryland | Delaware | 90%
|
| S | Gibraltar | Spain | 89%
|
| V | New Hampshire | Vermont | 89%
|
| F | Suriname | French Guiana | 88%
|
| H | Croatia | Hungary | 88%
|
| K | Iraq | Kuwait | 88%
|
| I | Washington | Idaho | 86%
|
| U | Crimea | Ukraine | 85%
|
| M | Arkansas | Missouri | 84%
|
| O | Arkansas | Oklahoma | 83%
|
| Y | Alaska | Yukon | 74%
|
| A | Mexico | Arizona | 64%
|
| C | Aragon | Catalonia | 47%
|
| T | Sichuan | Tibet | 39%
|
| B | Quintana Roo | Belize | 34%
|
| X | Quinghai | Xinjiang | 15%
|