| Castelnau-Tursan | |
| Commune Status: | Commune |
| Arrondissement: | Mont-de-Marsan |
| Canton: | Chalosse Tursan |
| Insee: | 40072 |
| Postal Code: | 40320 |
| Mayor: | Roland Guichane[1] |
| Term: | 2020 - 2026 |
| Coordinates: | 43.6589°N -0.4058°W |
| Elevation M: | 176 |
| Elevation Min M: | 74 |
| Elevation Max M: | 179 |
| Area Km2: | 9.27 |
Castelnau-Tursan (pronounced as /fr/; oc-gascon|Castèthnau de Tursan) is a commune in the Landes department in Nouvelle-Aquitaine in southwestern France.[2]
The wines of the surrounding countryside are known under the name Tursan.