| Châtelaillon-Plage | |
| Commune Status: | Commune |
| Image Flag: | Flag of Chatelaillon-Plage.svg |
| Image Coat Of Arms: | Blason ville fr Châtelaillon-Plage 17.svg |
| Arrondissement: | La Rochelle |
| Canton: | Châtelaillon-Plage |
| Insee: | 17094 |
| Postal Code: | 17340 |
| Mayor: | Stéphane Villain[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | CA La Rochelle |
| Coordinates: | 46.0742°N -1.0867°W |
| Elevation M: | 3 |
| Elevation Min M: | 0 |
| Elevation Max M: | 21 |
| Area Km2: | 6.59 |
| Population Demonym: | Châtelaillonnais.e (French) |
Châtelaillon-Plage (pronounced as /fr/, also pronounced as /fr/), commonly known as Châtelaillon, is a commune in the Charente-Maritime department, administrative region of Nouvelle-Aquitaine, France.
It is located south of the city of La Rochelle and is also a suburb. It is twinned with Knebworth, England.
In the 16th century near the point of Cornard today featured a fortress known as Castrum Allionis, the old capital of Aunis. On August 1130, the Duke of Aquitaine William X of Poitiers, besieged the château. The leader of the place Isembert deprived its troops. The rest of the fortress were totally despaired in the 16th century, a small hamlet with bells of the swamps. During the 19th century, it had agricultural area in Boucholeurs. At the end of the nineteenth century, it was linked with rail, it constructed its first baths bains de mar with numerous villas.
Today, the location of the mediaeval château is uncertain, it may also located by the Turge.
See also: List of twin towns and sister cities in France.
Châtelaillon is twinned with Knebworth, Hertfordshire, England,[2] and Evolène, Wallis, Switzerland, and Skierniewice, Łódź, Poland.