城墙 + Modifier / Standalone
The noun 城墙 (chéngqiáng) means "city wall," referring to the defensive walls that historically surrounded Chinese cities. It can also be used metaphorically to describe a protective barrier. For example, 爱的城墙 means "a wall of love" as a figurative expression.
西安的古城墙是中国保存最完整的。
xī'ān de gǔ chéngqiáng shì zhōngguó bǎocún zuì wánzhěng de.
The ancient city wall of Xi'an is the best preserved in China.
我们沿着城墙走了一圈,风景很美。
wǒmen yánzhe chéngqiáng zǒu le yī quān, fēngjǐng hěn měi.
We walked all the way around the city wall, and the scenery was beautiful.
这座城墙已经有六百多年的历史了。
zhè zuò chéngqiáng yǐjīng yǒu liùbǎi duō nián de lìshǐ le.
This city wall already has over six hundred years of history.