Oastkern is een straat te Kootstertille in de gemeente Achtkarspelen en is gelegen in de Nederlandse provincie Friesland.
| Postcode | Huisnummers |
|---|---|
| 9288 XJ | 18, 19, 21A, 21, 22, 24, 25A, 25, 26A, 26, 27, 28, 29A, 29, 30, 31, 33, 37, 37, 39, 41, 43A, 43, 45, 47, 49A, 51, 53, 55, 57, 59, 61, 63, 17, 16, 16D, 16C, 16B, 16A, 15, 14, 13, 12, 11, 10, 10B, 10A, 9, 8A, 7, 6, 5, 4, 3, 3B, 2, 1; |