Chemin de ronde

"Chemin the ronde" is French for "battlements".[1]

Battlements are walls, with spaces between them, through which defenders can shoot.[2]

Battlements on the Great Wall of China

https://en.wikipedia.org/wiki/Battlement#/media/File:Badalingchangcheng.JPG

[1] "Chemin de ronde," Oxford Dictionaries. http://www.oxforddictionaries.com/translate/french-english/chemin

[2] "Battlements," Cambridge Dictionaries Online. http://dictionary.cambridge.org/de/worterbuch/englisch/battlements