21723 is the Postal Code/PLZ Code for Hollern-Twielenfleth in the Germany State of Lower Saxony and the District of Landkreis Stade.
| Postal Code | 21723 |
| Postal Code Name | Hollern-Twielenfleth |
| State | Lower Saxony |
| District | Landkreis Stade |
| Timezone | Central European Summer Time (CEST) |
| Adjacent Postal Codes | 21680 21683 21684 21720 |