The proper noun 马德里 (Mǎdélǐ) is the Chinese transliteration of "Madrid," the capital city of Spain. It is a phonetic borrowing using characters chosen for their sound rather than meaning. You will often see it in sports and international news contexts.
马德里是一座充满活力的城市。
Mǎdélǐ shì yī zuò chōngmǎn huólì de chéngshì.
Madrid is a city full of vitality.
他下个月要去马德里出差。
Tā xià gè yuè yào qù Mǎdélǐ chūchāi.
He is going to Madrid on a business trip next month.
马德里的夏天非常炎热。
Mǎdélǐ de xiàtiān fēicháng yánrè.
Summers in Madrid are extremely hot.