10992
I think it's referring to an area of woodland, the number following Cpt on the sign linked at https://streetcomplete.app/p/75231.jpg is it's ID (and P meaning planted).

I'm not sure what the most appropriate tag for that is, I'll have another look and close this note if I find something.

Photo archived at https://web.archive.org/web/20250228183021/https://streetcomplete.app/p/75231.jpg