Passage: Chang'an ([ʈʂʰǎŋ.án] (listen); simplified Chinese: 长安; traditional Chinese: 長安) was an ancient capital of more than ten dynasties in Chinese history, today known as Xi'an. Chang'an means "Perpetual Peace" in Classical Chinese since it was a capital that was repeatedly used by new Chinese rulers. During the short-lived Xin dynasty, the city was renamed "Constant Peace" (Chinese: 常安; pinyin: Cháng'ān); the old name was later restored. By the time of the Ming dynasty, a new walled city named Xi'an, meaning "Western Peace", was built at the Sui and Tang dynasty city's site, which has remained its name to the present day.

Question: What was the name of the capital of China ten dynasties ago?
Chang'an