钟楼钟鼓楼从元大都开始，逐渐成为中国古代城市最突出的标志建筑之一。

Bell tower started from Dadu, the capital of The Yuan dynasty and gradually became one of the remarkable buildings in ancient China.

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因而西安钟楼已有1300年历史，是中国现存历史最悠久的钟楼，也是规模最大，最完整的钟楼。

So, Bell Tower in xi 'an has been 1300 years, the longest existing one in Chinese history, and also the biggest and most complete one.

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