| Uniqueness | Member State | Extra info |
| ...to completely surround two countries? | |
| ...to use the cyrillic script? | |
| ...with a legally defined language border? | |
| ...that switched currency to the euro in 2009? | |
| ...whose capital starts and ends with the same letter? | |
| ...that was part of Yugoslavia? | |
| ...through which the 70th parallel north runs? | |
| ...whose flag is virtually identical to that of a non-EU country? | |
| ...that has speed limits in miles per hour? | |
| ...to have a lake more than 5000 km² in area? | |
| ...that has EU-territory in the UTC-1 time zone? | |
| ...with no point more than 250m above sea level? | |
| ...that has an internet country code consisting of the same letter twice? | |
| ...with a musical instrument in its coat of arms? | |