The museum tour guide pointed out the old retrenchment behind the castle's outer wall.

博物館導覽員指出城堡外牆後方那道古老的內堡。

Our travel brochure features photos of the fort's stone retrenchment, restored last spring.

我們的旅遊手冊刊登了該要塞石造內層工事的照片，去年春天才修復完成。

The heritage consultant emailed a report on repairing the crumbling retrenchments at the site.

文化資產顧問寄來一份報告，說明如何修復遺址中崩塌的內層工事。