Châtel-Guyon
Prior to June 2008 it was officially known as Châtelguyon, the change in the official styling being an adoption of its colloquial spelling, as, for example, used by Guy de Maupassant in his 1884 short story, "Le tic".
First World War
At the time of the First World War, the population was approximately 2000 residents. It was an international destination for its baths and healing springs and attracted 30,000 visitors each summer. With the onset of war the majority of the hotels were closed. Many were used by the French government for housing French and Belgian refugees, as well as for hospitals by French and other forces. The American Expeditionary Force established Base Hospital No. 20 at Châtel-Guyon in May 1918. The hospital ceased operations in January 1919.
Population
| Year | Pop. | ±% p.a. |
|---|---|---|
| 1968 | 3,652 | — |
| 1975 | 3,530 | −0.48% |
| 1982 | 4,386 | +3.15% |
| 1990 | 4,743 | +0.98% |
| 1999 | 5,241 | +1.12% |
| 2007 | 6,224 | +2.17% |
| 2012 | 6,100 | −0.40% |
| 2017 | 6,152 | +0.17% |
| Source: INSEE | ||