| Name | Country | 14C dates | |
|---|---|---|---|
|
501-520 / 735 show all | |||
| Northumberland | United Kingdom | 3 | Show |
| Northumberland | England | 0 | Show |
| North Yorkshire | United Kingdom | 0 | Show |
| North Yorkshire | England | 0 | Show |
| Nottinghamshire | England | 0 | Show |
| Oberösterreich | Austria | 2 | Show |
| Offaly | Ireland | 13 | Show |
| Olmütz / Olomoucký kraj | Czech Republic | 0 | Show |
| Olomoucký Kraj | Czech Republic | 21 | Show |
| Olomouc Region | Czech Republic | 14 | Show |
| Oltenia | Romania | 0 | Show |
| Omagh | Northern Ireland | 0 | Show |
| Opole | Czech Republic | 0 | Show |
| opolskie | Poland | 3 | Show |
| Oppeln/Oppolskie | Poland | 0 | Show |
| Örebro | Sweden | 31 | Show |
| Orkney | United Kingdom | 1 | Show |
| Östergötland | Sweden | 70 | Show |
| Östergötlands län | Sweden | 1 | Show |
| Østfold | Norway | 3 | Show |
