What is the fine-grained topic of the following text: Being built during the reign of Qianlong during the Qing Dynasty (1644 - 1911), this 240-rooms compound has history dating back over 300 years and covers an area of over 5300 square meters (6340 square yards); yet it is only one-fifth of the Qu family's estate. Only return the topic.
Qing Dynasty Qu family estate